Resins, low temperature formulations, and coatings derived therefrom

ABSTRACT

A series of resins were synthesized using a range of bio-based materials to control the molecular architecture, and therefore the properties, of the inventive resins. The utility of these resins was demonstrated in the formulation of powder coatings, such as β-hydroxy amide crosslinked and hybrid types. Generally, the bio-based resins flowed out on heating faster than conventional petrochemically-based resins, allowing the use of lower temperatures in the curing oven than is typically possible and a more active catalyst system, especially in the carboxylic acid-epoxy crosslinked hybrid coating formulations.

This application claims the benefits of Provisional Application No.60/663,422 filed Mar. 18, 2005; and Provisional Application No.60/758,757 filed Jan. 13, 2006.

The entire contents of the two provisional applications are incorporatedby reference herein.

FIELD OF THE INVENTION

The invention is useful for producing powder coatings for substratesparticularly temperature sensitive substrates. Typical temperaturesensitive substrates include organic substrates including but notlimited to polymers such as plastics, and composites including but notlimited to wood and plastic composites.

BACKGROUND OF THE INVENTION

Current powder coating resins and formulations have one seriouslimitation: They generally need fairly high oven temperature (typicallyabove 177° C. to have the good flow and cross-linking required foracceptable performance. Many of the substrates to be coated—such asplastics, wood and bio-composites—are quite temperature sensitive andcannot tolerate the high temperatures used in current powder coatingsformulations. The use of such substrates has seen a significant increasein the last several years and is expected to grow quite dramatically inthe future. See the Muthiah reference for an example of recent work inthe area of low temperature cure powder coatings.

There is a need for a durable, cost-effective low temperature thermallycured powder coatings for temperature-sensitive substrates that also canbe used on high temperature substrates such as metals. In such cases,lower temperature would lead to lower energy cost in the process. Lowercosts should significantly increase the acceptance of the newtechnology.

There is a great deal of interest in the replacement of somepetrochemical feedstocks with bio-based feedstocks for use in a widerange of application areas. Evidence of this interest is reflected inthe number of review articles that have been published through theyears. Efforts to utilize bio-based feedstock in the synthesis ofpolyester resins is exemplified in U.S. Pat. No. 6,063,464 and in thepaper by Guo, et. al. (see below), wherein corn bio-mass derivedisosorbide is used in the synthesis of polyester materials.

There is also a need to produce powder coatings that flow-out and cureat lower temperatures than those currently used in the industry. Powdercoatings offer environmental advantages in that they are very low inin-use emissions of VOCs. Unfortunately, some of that advantage is lostdue to high energy demands in the cure cycle and the rough finishestypically derived from them owing to poor flow-out at low temperatures.

Other related patents and journal articles include;

-   LOW TEMPERATURE CURE: U.S. Pat. No. 6,703,070 March 2004 Muthiah-   SYNTHESIS AND PROCESSING: EP1491593 December 2004 Mons-   BIO-BASED MATERIALS REVIEWS: Applied Microbiology and Biotechnology    (2001), 55(4), 387-394. Huttermann, A.; Mai, C.; Kharazipour, A.    “Modification of lignin for the production of new compounded    materials”;-   Biopolymers from Renewable Resources (1998), 1-29. Kaplan, David L.    “Introduction to biopolymers from renewable resources”;-   Bioresource Technology (1994), 49(1), 1-6. Sharma, D. K.; Tiwari,    M.; Behera, B. K. “Review of integrated processes to get value-added    chemicals and fuels from petrocrops”; and-   Applied Biochemistry and Biotechnology (1988), 17 7-22. Narayan,    Ramani. “Preparation of bio-based polymers for materials    applications”.-   BIO-BASED RESIN SYNTHESIS: Abstracts of Papers, 224th ACS National    Meeting, Boston, Mass., United States, Aug. 18-22, 2002 (2002). Guo,    Yinzhong; Mannari, Vijaykumar M.; Massingill, John L., Jr.    “Hyperbranched bio-based polyols”.-   POWDER COATINGS: “Powder Coatings Volume 1: The Technology,    Formulation, and Application of Powder Coatings”. Howell, David M.    John Wiley and Sons, London, 2000.-   Polymer Preprints 2003, 44(1). Gedan-Smolka, Michaela; Lehmann,    Dieter; Lehmann, Frank. “Catalysis in Uretdione Powder Coatings    Enables Innovative Processing Lines”.

In addition to the need for low temperature flow and cure in powdercoatings, there is also a need for good dispersion of pigments within acoating matrix, regardless of the coating type. To accomplish this,polymers are designed that have components with differingcompatibilities. Polymeric dispersants stabilize pigments and otheringredients in paints, coatings, and ink systems via, most typically,steric stabilization. Polymeric dispersants have a two-componentstructure comprised of anchoring groups and polymeric chains. Mosttypically the anchoring groups are polar materials that interact withthe is particle surfaces and the polymeric chains which are compatiblewith the continuous phase of the coating. In effect, the polymericgroups form a coating around the particles, preventing them from makingcontact and agglomerating into larger, incompatible aggregates.

There are many anchoring group/polymer configurations that might beexpected to give effective polymeric dispersants. The inventive resinhas polar carboxylic anchoring sites and non-polar vegetable oil chainsand can therefore act as a dispersant as well as a binder. A curingbinder that can also act as a dispersant could eliminate the need forseparate additives for dispersing many pigments. Related art includesU.S. Pat. No. 5,959,066; U.S. Pat. No. 6,025,061; U.S. Pat. No.6,063,464; and U.S. Pat. No. 6,107,447.

BRIEF DESCRIPTION OF THE INVENTION

Briefly, there is a need for a durable, cost-effective low temperaturethermally cured powder coating for temperature-sensitive substrates thatalso can be used on high temperature substrates such as metals. There isa further need to find replacement materials for petrochemicalfeedstocks, especially when abundant bio-based feedstocks can beutilized in this replacement. The bio-based powder coatings technologydisclosed herein meets this need by combining novel resin derived fromrenewable bio-source and proprietary formulation technologies,especially low temperature cure technologies. In the latter cases, lowertemperature would lead to lower energy cost in the process, and shouldsignificantly increase the acceptance of the new bio-based technology.

One embodiment of the invention provides for the synthesis of polyesterresins that have a Tg greater than 50° C., a bio-based content of atleast 5% and in another at least 50%, and relatively low viscosity.

In broad embodiments, the resins are utilized in the formulation ofcoatings, especially powder coatings.

In a further embodiment the resin includes carboxylic functionalpolyesters from the reaction on diacids and diols.

In a further embodiment the acids and diols utilized to form thepolyester resins are bio-based or petroleum based as needed in order tomaximize the properties of the resultant coatings and to maximize theamount of bio-based material in the resins.

In yet further embodiments of the invention, the resins are compoundedwith crosslinking resins for curing into protective coating films withgood flow and flexibility, often at relatively low temperatures.

In yet further embodiments of the invention, the resins are compoundedwith PRIMID resins for curing into protective coating films with goodflow and flexibility.

In yet further embodiments of the invention, the resins are compoundedwith acrylic epoxy resins for curing into hybrid powder coating filmswith good flow and flexibility, at relatively low temperatures.

In a further embodiment the formulations include catalysts, flow controlagents, cure modifying additives and the like to control appearance,cure rate, and other properties.

In a further embodiment the formulations include catalysts comprised ofimidazole and substituted imidazoles.

In a further embodiment the formulations include cure modifyingadditives such as acidic additives to modify the activity of theimidazole and substituted imidazole catalysts.

In further embodiment the formulations may contain additives andexcipients known in the art including pigments for color, appearance,corrosion control, hiding, or other functions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic flowchart that shows a synthetic pathway towardpolyester materials blending hard, crystalline isosorbide with amorphousdimer diols, aromatic diesters and other ingredients.

FIG. 2 is a schematic flowchart that shows a synthetic pathway towardpolyester acids blending hard, crystalline isosorbide with amorphousdimer diacids and other ingredients. These can be utilized specificallyin hybrid powder coatings formulations to crosslink epoxy functionalsites.

FIG. 3 is a schematic flow chart that shows a synthetic pathway towardpolyurethanes blending hard, crystalline isosorbide with dimer amorphousdimer diacids, polyisocyanates (e.g. diisocyanate), and otheringredients.

FIG. 3A illustrates typical isomers of isosorbide—1a, 1b, and 1c thatare useful with the invention.

FIG. 4 is a graph that illustrates rheology curves for a bio-based resin(Example 2) and a typical commercial resin (FINE-CLAD 8400®).

FIG. 5 is a graph illustrating viscosity profiles of a bio-basedformulation (Example 4A and a commercial control formulation at about121° C.

FIG. 6 is a schematic drawing showing the various elements of theapparatus used for making resin examples 1 through 3F.

FIG. 7 is a bar graph showing the viscosities for formulations A to G ofExample 8 at 90° C. and 100° C.

DETAILED DESCRIPTION OF THE INVENTION AND BEST MODE

Broadly the invention combines the desired use of bio-based feedstockwith the need for lower temperature powder coatings. Corn and soyfeedstocks can be utilized to make resins with a balance of propertiesappropriate to powder coating performance. These resins can then beformulated into a variety of powder coating formulations.

Typically, a powder coating formulation according to the invention isprepared by: Pulverizing the principal resin, dry blending with apulverized hardener and selected pulverized additives, melt-mixing thedry blend, extruding the melt-mixed blend, followed by rapid cooling.The cooled blend is then pulverized to a desired particle size, andfinally the resulting powder is classified into the final particle size.

Bio-based feedstocks, formulations, products, materials, resins and thelike, as used herein for some embodiments of the invention, meansfeedstocks, formulations, materials, resin, and products and the likethat are derived at least in part from conversion of agricultural andforest based renewable resources processed by conventional chemicalmodifications and/or by biological processes such as fermentation. Thecarbon source is derived from a renewable plant crop/tree resourceunlike conventional fossil derived carbon source that is finite and isdepleting.

Hybrid resins as used herein means that the resin is a blend of morethan one type of resin, for example polyester and epoxy.

A resin that is particularly useful according to the present inventionhas a good balance of two apparently contradictory properties:

(1) A low viscosity at melt for good flow-out on application, which ischaracteristic of amorphous resins, but must also have,(2) A relatively high glass transition temperature (T_(g)) for goodstorage stability, characteristic of crystalline resins. If the Tg istoo low, the powder particles will be “soft” and will coalesce into anunusable mass on storage, especially at elevated storage temperatures.Typically, these properties are balanced by blending crystalline andamorphous resins into effectively semi-crystalline resin blends.Typically resins obtained according to the present invention providethese desired properties.

Note: Unless otherwise specified % when referring to the amount of aningredient refers to weight percent (wt %).

There are four general approaches for resin synthesis disclosed herein:

1. Hydroxyl functional polyesters based upon dimer diols,isosorbide-derived diols and/or dimer acids. Typically the carboxyl orhydroxyl functionality of the polyester is determined by the ratio ofthe molar excess of either the diacid or the diol groups. The polyesterstypically have a net bio-based content of at least about 5 wt %, butmost typically about 20 to about 50 wt %2. Carboxyl functional polyesters based upon dimer diols,isosorbide-derived diols and/or dimer acids. Typically the carboxyl orhydroxyl functionality of the polyester is determined by the ratio ofthe molar excess of either the diacid or the diol groups. The polyesterstypically have a net bio-based content of at least about 5 wt %, butmost typically about 50 to about 70 wt %3. Hydroxyl, carboxyl, or isocyanate functional polyurethanes based upondimer acids and/or dimer diols. Typically excess isosorbide and/or dimerdiol produces hydroxyl functionality and excess dimer acid producescarboxyl functionality, and excess polyisocyanate produces isocyanatefunctionality. The polyurethanes typically have a net bio-based contentof at least about 5 w %, but most typically about 20 to about 50 wt %.4. Amido-amine functional resins as disclosed in WO 2004/077169, forReadily Deinkable Toners, filed Feb. 2, 2004, and designating the UnitedStates. The amido-amine resins are a reaction product of dimer acid anddiamine as described in the patent application the contents of which areincorporated by reference herein. In some embodiments of the presentinvention typical amido amine functional resins have a Tg of less thanabout 80° C. In other embodiments of the present invention theamido-amines have a Tg of less than about 70° C. The net bio-basedcontent is typically at least 5 wt %, but more typically at about 40 toabout 60 wt %

Resins according to the invention can be comprised of co-reactedcomponents that tend to contribute rigidifying effects, such asisosorbide (typically from corn feedstock), and components thatcontribute flexiblizing effects, such as dimer acid or dimer diol(typically from vegetable oil feedstocks). By appropriately co-reactingthese components into resins both the flow-out and storage stability ofthe resin can be controlled. In general, rigidifying components containfunctional chemical groups, such as alcohol, ester, carboxylic acid oracid chloride, attached to a cyclic structure which limits theirmobility whereas the flexiblizing components contain functional chemicalgroups attached to aliphatic carbon chains. Isosorbide is a diolcomprised of fused cyclic ether rings and is a member of a larger familyof bio-based sugar derivatives commonly referred to asdianhydrohexitols. Dimer acid and dimer diol are di-carboxylic acids anddi-alcohols, respectively, derived from bio-based fatty acids which arelargely aliphatic in nature. Similarly these rigidifying andflexiblizing effects may also apply to polyurethanes as depicted in FIG.3.

The resins are typically cured by crosslinking with a catalyst and/orheat. Typical cure temperatures are up to 125° C.

The polyester polyol resins disclosed herein are useful in coatings,adhesives, sealants and other applications in reactive formulations withisocyanates, epoxies, melamine formaldehydes, urea formaldehydes andothers.

Poly carboxylic resins disclosed herein are useful in coatings,adhesives, sealants and other applications in reactive formulations withβ-hydroxylamides, epoxies, and others.

Amido-amine functional resins are useful in coatings, adhesives,sealants and other applications in reactive formulations withisocyanates, epoxies, melamine formaldehydes, urea formaldehydes andothers.

Of particular usefulness are the disclosed bio-derived resins in powdercoating formulations. Example 4 describes a bio-derived carboxylicfunctional resin cured in a transesterification manner with aβ-hydroxylamide in a powder coating formulation to form a clear coating.Example 4A describes a resin similar to that in Example 4, however theresin has been made in a larger scale. The obtained resin has a slightlyhigher Tg. Example 5 describes a bio-derived carboxylic functional resincured with an acrylic epoxy resin in a powder coating formulation toform a clear coating. Example 6 describes a bio-derived carboxylicfunctional resin cured with a commercial epoxy crosslinking resin in apigmented powder coating formulation to form a black colored coating.Example 6A describes pigment dispersions comprised of a bioderivedcarboxylic acid functional resin and carbon black as compared to acommercial carboxylic functional resin and carbon black and their effecton color when added to a white powder coating formulation. Example 6Bdescribes a bio-based carboxylic acid functional resin cured withtriglycidyl isocyanurate (TGIC) crosslinker.

Example 7 describes a bio-derived amido-amine functional resin curedwith a commercial epoxy crosslinking resin in a powder coatingformulation to form a clear coating.

Example 8 illustrates the production of a powder coating using abio-based polyester as a flow promoter. The polyester resin is describedin Example 3B.

Example 9, the final example, illustrates pigment dispersion propertiesof a resin prepared according to Example 3F.

One embodiment of the present invention concerns a process for themanufacture of resins for powder coating application from a minimum to amaximum amount of bio-based materials. The resins in another embodimentof the invention include at least one saturated or unsaturated bio-basedpolyester.

The present invention also pertains to the use of one or more of thesebio-based materials in a variety of applications including, but notlimited to coatings, powder coatings, adhesives, toners, inks, sealants,polymer additives, and others. Resins for one embodiment were designedthat would have a glass transition temperature (T_(g)) of less thanabout 80° C., other embodiments having a glass transition temperature ofless than about 70° C., yet further embodiments of less than about 60°C., with appropriate melt rheology. A resin according to a broad generalembodiment of the invention has a minimum glass transition temperatureof at least about 20° C. and a maximum of about 80° C., with appropriatemelt rheology. Resins useful for flow control typically are at the lowerend of the glass transition temperature range (e.g. Example 3B where theTg is about 28.4° C.), however they can range from about 20° C. to about80° C., and on some embodiments can typically be about 25° C. to about60° C.

Hybrid powder coatings resins comprised of inventive resins containinggreater than 50% bio-based and carboxy functional groups were formulatedinto powder coatings. The inventive resins described herein arecomprised of co-reacted components that tend to be hard and highlyfunctional, such as isosorbide (typically from corn feedstock), andcomponents that tend to be soft and flexible, such as dimer acids(typically from soybean feedstock). By appropriately co-reacting thesecomponents into resins both the flow-out and storage stability can becontrolled.

The present invention also concerns the formulation of a powder coatingfrom the one or more inventive resins. A distinguishing characteristicof this powder coating is the ability of this coating to flow-out andcure into a continuous film at temperatures lower than typical forpowder coating operations. The low temperature curing capability derivesfrom the low-viscosity nature of the bio-based resin utilized in itscomposition and a formulation that exploits the advantageous flowcharacteristics of the inventive resinous component. The advantageobtained from the inventive resin is the low viscosity at a giventemperature when compared to an approximately equivalent commercialresin.

A key characteristic of resins used in powder coatings formulations isthe glass transition temperature (T_(g)) which is typically at leastabout 50° C. and preferable at least about 60° C. for storage stabilityof the ultimate powder coating powder. Table 1 shows a list of severalsoy-based resins, their functionality, and their T_(g). This Tableillustrates the difficulty of producing a resin with an acceptable T_(g)from materials that include low-viscosity soy-based monomers.

TABLE 1 Soy-based resins Tg (° C.) Resin No. Functionality (ifavailable) R-1 Amido-amine 61 R-2 Hydroxyl 45 R-3 Hydroxyl 28 R-4 100%Hydrogenated Waxy Polyester polyol R-5  50% Hydrogenated Waxy Polyesterpolyol R-6 Polyester Waxy

Only Resin 1-1 met the criteria for T_(g). To achieve higher T₉s in thepresence of soy-based materials and maintain a high loading of bio-basedmaterial in the resins, isosorbide, another bio-based material, but onewith high inherent T_(g) contribution was utilized.

A higher T_(g), bio-based material (isosorbide, derived from cornfeedstock) was identified that could be co-reacted with the soy-basedmaterials to give to resins with a high bio-based content and asufficiently high T_(g) for powder coating formulations. Subsequentsyntheses sought to balance the soy, the isosorbide and otheringredients to achieve an appropriate balance of properties in theresins and, ultimately, in the powder coatings.

Resin Synthesis (See Examples 1 and 2):

The use of bio-based materials in the production of coatings can bedescribed as follows:

A polyester polymer is prepared by (1) mixing in a reactor isosorbide(derived from corn feedstock); fatty dimer diol and/or dimer diacid(derived from soybean feedstock); a diacid, diester, or diacid chloride;optional co-diol(s); and optional co-diacid(s), co-diester(s) orco-diacid chloride(s), with a condensation catalyst suitable forpolymerizing aromatic diacids and diols; and (2) heating the monomersand catalyst to polymerize the monomers to yield a polyester. (See FIG.1)

A carboxyl functional polyester resin is prepared by (1) mixing in areactor isosorbide; fatty dimer diacid; optional co-diacid(s),co-diester(s) or co-diacid chloride(s); and optional co-diol(s); with acondensation catalyst; and (2) heating the monomers and catalyst topolymerize the monomers to yield a carboxyl functional polyester resin.(See FIG. 2)

A hydroxyl, carboxyl, or isocyanate functional polyurethane is preparedby (1) mixing in a reactor isosorbide; fatty dimer diacid and/or dimerdiol; a polyisocyanate; optional co-diol(s); and optional co-diacid(s),co-diester(s), or co-diacid chloride(s), with or without a catalystsuitable for polymerizing diols and diacids with polyisocyanates; and(2) heating the monomers and optional catalyst to polymerize themonomers to yield a polyurethane. (See FIG. 3)

Referring now to FIGS. 1, 2, and 3 that disclose various reactants isuseful for the embodiments herein. In addition to the disclosed dimerdiols and dimer acids the invention according to a broad embodimentincludes aliphatic chains typically having from about 4 to about 20carbon atoms. More preferably, the aliphatic chains have about 6 toabout 16 carbon atoms.

The additional disclosed dimer diols and dimer acids include a sixmember ring with two side chains being an aliphatic side chain of about4 to 20 carbon atoms and the other two side chains of about 8 to 12carbon atoms with an alcohol or carboxylic functional group.

Additionally, the diesters, diacids, co-diacids and co-diesters may havethe formula R₂—CO—R₁—CO—R₂ wherein R₂═—OH, —OR₃, or —Cl, wherein R₃=analiphatic chain having from one to four carbon atoms. R₁ is an aromaticor an aliphatic group having 2-12 carbon atoms.

Although not wishing to be bound by theory, it is presently believedthat the aliphatic side chains in the dimer acid and dimer dial providea low viscosity properly for the resins. The aliphatic side chains tendto soften at low temperatures causing lowered viscosity and better flow.The longer the chain the more softening will be seen and the faster itwill soften on heating.

They are also believed to provide in some embodiments improved pigmentdispersion as illustrated in Example 9. One consequence of better flowis superior wetting of pigment, thereby improving pigment dispersion.

Additionally and more broadly, dihanhydrohexitols can be use din theinvention. Thus other dianhydrohexitols can replace D-isosorbide or itsisomers in preparing rigidifying structures by means of incorporatingbicyclic containing other cyclic diols can be used in the invention.Diols incorporating cyclohexyl, isophorone, and other cyclic structurescan add the rigidifying effect similar to isosorbide.

Dimer diacids are typically viscous liquids produced by the dimerizationof C₁₈ unsaturated fatty acids. There are three biosources of C₁₈unsaturated fatty acids; vegetable, tall oil, and animal. The C₁₈ unitscan be linked together in several ways. Four main structural types areknown for the predominant component, the C₃₆ diacids; acyclic,monocyclic, bicyclic, and aromatic. There are also many structuralisomers for each of these structural types. The distribution of thesestructural types and isomers is dependent on the mono/poly-unsaturationratio of the starting fatty acid feedstock and the process conditionsemployed for dimerization. The smallest dimer diacid typically used insome embodiments is a C₁₈ diacid.

Four types of dimer diacids are currently commercially available; (1)standard (undistilled), which contain about 80% C₃₆ dibasic acids, (2)distilled, in which the C₃₆ dibasic acid content has been enhanced to92-98%, (3) distilled and partially hydrogenated for improved color, and(4) distilled and fully hydrogenated for maximum stability.

Typical dimer acids used to prepare the bio-based polyester resins wereEmpol 1018® (Examples 3, 3C, and 3E) and Pripol 1013® (Examples 2, 3A,and 3D), both vegetable-based dimer acids. Empol 1018® is manufacturedby Cognis Corporation and Pripol 1013® is manufactured by Uniqema.Cognis has since discontinued their vegetable-based dimer acidproduction in favor of tall oil-based dimer acid. Table 3 compares thephysical properties and composition of Pripol 1013® and Empol 1018®.Pripol 1013® is lighter in color and has a higher dibasic acid content.The resultant carboxyl functional resins using the two different dimeracids had similar physical properties.

TABLE 1A Dimer Acid Compositions and Properties Empol ® 1018 Pripol ®1013 Dimer Acid (Batch # U42G151910) (Batch # 091687) Acid Value 193.5195 Color, Gardner 8 3-4 Composition wt % Monobasic Acid 5 0.1 wt %Dibasic Acid 81 97 wt % Polybasic Acid 14 3

Dimer diol is typically produced by high-pressure hydrogenation of dimerdiacid methyl ester. The dimer diol used to prepare the bio-basedpolyester resins (Example 1, 1A, and 3B) was SPEZIOL C36/2 1075® dimerdiol. This is a vegetable-based dimer diol produced by Cognis.

The resins disclosed herein have low viscosity relative to commercialpetrochemically-based resins once melted (see examples). In currentcommercial resin powder coating formulations, it is necessary to addflowable materials (flow control additives) in order to get goodflow-out and leveling of the resultant film after the cure cycle. Thebio-based resins require little or no such additives to achieve goodfilm leveling and appearance. The bio-based resins can also function asflow additives themselves in formulations containing conventionalpetrochemically-based resins in which they were successfullyincorporated. Typically, a bio-based resin content of about 0.1 wt % toabout 5 wt % is used for the purpose of utilizing the flow controlproperties of the inventive resins in conjunction with using other mainpowder resins for coating formulations.

The inventive polyester polymers were prepared by melt polymerization ofisosorbide, dimer diol and/or dimer acid, a diacid, diester, or diacidchloride; optional co-diol(s); and optional Co-diacid(s), co-diester(s)or co-diacid chloride(s) (Method from FIG. 1)

A typical procedure used to prepare the inventive polyesters isdescribed in Example 1. Aliphatic polyesters are soft, flexible rubberymaterials. Most aromatic polyesters are crystalline. Blending the softdimer diols with the highly functional isosorbide and with thecrystalline aromatic di-acids results in a good balance of properties.This balance can be helped, however, by including other materials, suchas ethylene glycol in the reaction (i.e., as the “diol” in FIGS. 1 and2).

The effect of various monomers was studied by preparing polyesters withglass transition temperatures (T_(g)s) ranging from 61° C. to 165° C.(Tables 2A and 2B). Table 2A shows typical properties of resinssynthesized as described herein and the effects of various monomers thatwith glass transition temperatures (T_(g)s) ranging from 61° C. to 165°C. Table 2B shows typical properties of carboxyl functional resinssynthesized as described in examples 2-3A.

TABLE 2A Polyester polyols based on soy-derived dimer diol and/orcorn-derived isosorbide Dimer Diol Ethylene Dimethyl- Inherent AcidValue (mole Isosorbide Glycol terephthalate T_(g) Viscosity HydroxylValue (mg EXAMPLE %)^(a) (mole %) (mole %) (mole %) (° C.) (dl/g)^(b)(mg KOH/g) KOH/g) Example 1 5.8 14.9 27.8 51.5 61 0.29^(c) 23.3 8.0Example 1A 12.2 38.0 0 49.8 165 0.10 40.9 2.6 Example 3B 10.8 17.1 22.749.4 28.4 0.19 35.4 6.1 Notes ^(a)Dimer diol based polyester resin %compositions were calculated based upon the NMR of the final resin andare in mole % ^(b)Measured on a 1% (weight/volume) solution of thepolymer in o-chlorophenol at a temperature of 25° C. ^(c)Only 92%soluble in o-chlorophenol. ND = not determined

TABLE 2B Polyester carboxylic acids based on soy-derived dimer acid andcorn-derived isosorbide Acid Dimer 1,4- Inherent Value Acid IsosorbideCHDA T_(g) Viscosity Hydroxyl Value (mg Example # (wt %)^(a) (wt %) (wt%) (° C.) (dl/g)^(b) (mg KOH/g) KOH/g) Example 2 19.4 37.1 43.4 64.2 NDND 34.8 Example 3 16.1 38.4 45.5 66.9 0.25 13.0 36.3 Example 3A 18.837.6 43.6 65.3 ND ND 29.0 Notes ^(a)Dimer acid based polyester resincomposition calculations were based upon initial charge weights^(b)Measured on a 1% (weight/volume) solution of the polymer ino-chlorophenol at a temperature of 25° C. ND = not determined

The data shows the large range of T_(g)s possible with these monomers. Atest polyester prepared without isosorbide was not amorphous like thosecontaining isosorbide but was crystalline in behavior.

D-Isosorbide (1,4:3,6-dianhydro-D-glucitol) (1a) or isomers thereofand/or mixtures of all isomers, including D-Isosorbide, could be used inplace of D-Isosorbide. 1,4:3,6-dianhydro-D-mannitol (1b) and1,4:3,6-dianhydro-D-iditol (1c) are two isomers of Isosorbide.D-isosorbide was used in this invention but isomers of D-isosorbide areexpected to work as well. Isomers of isosorbide useful with theinvention are illustrated in FIG. 3A.

Examples of suitable polyols for forming the acid-functional polyesterinclude: 1,2-ethanediol (ethylene glycol), 1,3-propanediol,1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol,1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol,neopentyl glycol, trimethylolpropane, hydrogenated bisphenol A(2,2-(dicyclohexanol)propane), 2,2,4-trimethyl-1,3-pentanediol,2-methyl-1,3-propanediol, 2-methyl-2-hydroxymethyl-1,3-propanediol,2-ethyl-2-hydroxymethyl-1,3-propanediol and the like, and combinationscomprising at least one of the foregoing polyols. Since the current worktargets maximizing bio-based content, the preferred polyols areisosorbide (from corn stock) and dimer acid diol (from soybean stock),ethylene glycol and others may be used to enhance properties as needed.

Suitable polycarboxylic acids, acid esters and acid chlorides includethose derived from succinic acid, adipic acid, azelaic acid, sebacicacid, 1,12-dodecanedioic acid, terephthalic acid, isophthalic acid,trimesic acid, tetrahydrophthalic acid, hexahydrophthalic acid,1,4-cyclohexanedicarboxylic acid, trimellitic acid, naphthalenedicarboxylic acid, dimer acids, and the like, and combinationscomprising at least one of the foregoing polycarboxylic acids. Thepreferred diester is the dimethyl ester of terephthallic acid.Dodecanedioic acid (DDA) is used as a modifier in several formulations.Presently preferred are diacids such as 1,4-cyclohexanedicarboxylicacid, Empol 1018®, Pripol 1013°, and the like.

To obtain carboxyl-functional polyesters of desired molecular weight,the monomer mixture used to form the polyester typically has anappropriate excess of carboxyl functionality to hydroxyl functionalitywhere the ratio of hydroxyl equivalents over acid equivalents istypically 0.85-0.95. The polyesters may range from amorphous tocrystalline.

Crosslinking is achieved by reacting the carboxyl group of the carboxyfunctionality with either a β-hydroxylamide in a self catalyzedtrans-esterification reaction (often referred to as the PRIMID reactionafter the amide's trade name (Table 3) or with a commercial polyepoxyfunctional polymer. Preferred polyepoxy compounds, especially for lowtemperature cure compositions, are epoxy-functional acrylic ormethacrylic resins such as glycidyl acrylate or glycidyl methacrylatecopolymer (collectively, “GMA”) resins. GMA resins are typicallyobtained from about 5 to about 30 wt % of glycidyl acrylate or glycidylmethacrylate and about 80 to about 95 wt % of methyl methacrylate,wherein up to about 50 wt % of the methyl methacrylate can be replacedby another alpha, beta-unsaturated monomer, e.g., styrene,acrylonitrile, and the like. Suitable GMA resins have epoxy equivalentweights of about 200 to about 1000, preferably about 200 to about 600,and an Mn of 200 to about 2000 atomic mass units (AMU) as determined bygel permeation chromatography. They are solid at room temperature,having melting points above about 40° C., preferably a softening pointof about 50° C. to about 75° C., and a Tg of about 40° C. to about 60°C. (Table 3).

Given that low temperature flow-out can be achieved with the bio-basedresinous components, it is advantageous to utilize a catalyst thatinitiates cure at a temperature of from about 115° C. to about 140° C.,selectable from the many that are commercially available. Typically, acatalyst may be used at a level of from about 0.1 to about 5 parts perhundred parts of the resin (phr), preferably about 0.2-2 phr toaccelerate the curing reaction with the low temperature curing agent.Preferred catalysts for this invention are imidazoles and adductsthereof, the imidazoles having the general formula shown in Formula 1:

wherein R₁, R.₂, R₃, and R₄ are independently hydrogen, methyl, phenyl,or benzyl.

Broadly, the substituent may be any not reactive with the epoxy resin.Tertiary amines and poly-amine materials are also useful as catalystsfor this reaction.

To maintain good flowability, it may be necessary to modify thereactivity of the imidazole catalyst by creating an adduct that partlyblocks its reactivity. Sometimes this is accomplished by making anadduct of the imidazole with epoxies (see, for example U.S. Pat. No.6,703,070). In one embodiment of the present invention, the parentimidazole was the catalyst of choice and acidic materials were added tothe formulation to mitigate the reactivity of the imidazole.

Acidic materials that are suitable for mitigating the reactivity of theimidazole include aromatic sulfonates, such as benzene or naphthalenesulfonic acids and substituted variations thereof, aromaticcarboxylates, such as or naphthalene carboxylic acids and substitutedvariations thereof, solid acidic materials, such as inorganics orsuper-acids, may also be employed. In the latter cases, a portion of theimidazole catalyst may be adsorbed onto the solid acidic surface andtherefore made unavailable to the bulk of the binder until heated. Onesuch solid material, for example, is the blocked superacid NACURE® 7231(an ammonium antimonate) from King Industries.

The coating powder may also contain a flow control agent in the range offrom about 0 to about 5 wt % with the range from about 0.1 wt % to about2 wt % being most preferred. Examples of the flow control agents includethe MODAFLOW® poly(alkylacrylate) (i.e., MODAFLOW 6000®) products andothers such as the SURFYNOL® acetylenic diols (i.e., P200®) whichcontain hydroxyl, carboxyl or other functional groups. Thefunctionalized flow additives also aid intercoat adhesion in the eventthat touch-up or repair of the powder coating is necessary. The flowadditives may be used singly or in combination. Anti-oxidants may alsobe used at a concentration of from about 0.5 to about 2.0 phr to preventthe discoloration of the coatings even at the relatively low curingtemperatures suitable for the purposes of this invention. As mentionedelsewhere herein the inventive resin itself may act as a flow controlagent as exemplified by Example 3B resin in formulation Example 8.

Pigments such as titanium dioxide and/or carbon black, fillers such asto calcium carbonate, texturizing agents such as particulate rubber,bentonite clays, powdered polytetrafluoroethylene (PTFE) with or withoutpolyethylene powders, such as those sold under the trademark LANCOWAX®,and other conventional additives may also be present for appearance andto reduce cost.

Benzoin is typically used as an anti pin-holing additive (see the Howellis reference).

Table 3 shows a list of commercial powder coating resins describingtheir functionality and their T_(g). Some of these resins were used inthe preparation of the examples herein. The remainder have been used inother formulations and are also useful with the various embodiments ofthe invention.

TABLE 3 Commercial resins for formulation studies Resin FunctionalityT_(g) (° C.) FINE-CLAD ® M-8930 COON polyester 65 (Reichhold)FINE-CLAD ® A-257 (Reichhold) GMA acrylic epoxy, 50 dispersantFINE-CLAD ® A-253 (Reichhold) GMA acrylic epoxy 50 FINE-CLAD ® A-249-AGMA acrylic epoxy 64 (Reichhold) FINE-CLAD ® A-241 (Reichhold) Flowpromoter 66 RUCOTE ® 102 (Bayer) Polyester polyol 55 PRIMID ® XL 552β-Hydroxy amide 120 (PRIMID EMS ®) (melt point) PRIPOL ® 1013 (Unichema)Dimer acid Oil Dodecanedioic acid aliphatic diacid 127-129(DDA)(various) (melt)

A general procedure that can be adapted to prepare the powder coatingformulations according to the invention is described below:

Procedure: Powder Coating Mix Protocol: A Brabender® mixer is typicallyused, however, the procedure can be adapted for other types of mixers.

Calculate powder coating formulation to equal approximately 70 to 80 gbased on a 120 ml bowl size. A typical small Sigma Blade bowl holds 70 gunpigmented to low Pigment to Binder(P/B) coating formulation, or 80 gof a higher P/B paint.

Preheat a Brabender® mixer or similar mixer to 99° C. by starting oilheater. Allow 30 minutes to preheat.

When preheating is complete, start rotors and test security of the bowlto the instrument.

Turn on the torque sensor. This will act as a guide for how the mix isproceeding.

Add approximately 30 g of primary resin slowly to the bowl.

Allow the resin to mix and melt until the torque sensor shows a steadyvalue (about 5 minutes) then add any remaining primary resin slowly tomixing bowl and allow mixing and melting.

Add any/all additives to center of the mix zone between rotors.

Allow to mix until the torque value is stable (typically about 10minutes).

Slowly add all of the crosslinking resin to the bowl. Allow to mix atleast 3 minutes, make sure the torque reading remains stable in casecrosslinking starts (torque reading will start to rise rapidly).

Add catalyst (if called for) last, watching the torque reading closely.The torque should increase and the batch should be stopped after a 10%rise in viscosity (torque).

The product is quickly removed from the mixing bowl as a thick moltenmaterial and is cooled to the desired temperature (typically roomtemperature) till it is hard (it is typically a hard brittle shinymaterial).

After cooling to the desired temperature, the product is broken intosmall chips.

The chips are then ball milled or otherwise micronized (e.g. ball millpaint chips in presence of 10 mm-15 mm steel media for 16 hours) toobtain a fine powder.

The powder is sieved through appropriate screens to remove any largepieces, typically pieces larger than about 105 microns.

Utilizing the methods described, several classes of powder coatingsformulations can be prepared.

A general procedure for producing the finished powder coatings accordingto the invention is as follows.

The substrates are prepared for coating by wiping clean with a solventappropriate for the substrate (e.g. water, methyl ethyl ketone,isopropyl alcohol).

The substrates are grounded.

The powder coating is poured into the sample reservoir of a powder spraygun—such as the Versa-Spray® supplied by Nordson Corporation.

The voltage controls are adjusted on the spray gun control unit toensure the appropriate charge is applied to the powder.

The powder is applied via standard powder coating techniques to achievethe desired film thickness of approximately 50.8-76.2 microns (2-3 mils)dry film thickness.

The substrate is then placed in an oven for the appropriate time andtemperature.

Typically β-hydroxy amide based powder coatings are based upontransesterification crosslinking of a carboxyl functionality with adi-N-β-hydroxylamide crosslinker. These types of powders are exemplifiedby commercial PRIMID® type powders. Example 4 shows the details offormulation and cure of bio-based resin versus a conventionalpetrochemical based resin. This type of chemistry is insensitive tocatalysis, therefore no significant difference in cure rate wasexpected, and indeed, no cure speed advantage for either resin wasdetected in that case.

The two coatings were cured at two different temperatures, 121° C. and147° C. for 30 minutes. The biggest difference was the gloss at thehigher temperature, which was approximately 50 units higher for thebio-based resin formulation than for the control. Solvent resistance wasslightly lower for the bio-based formulation, however. Evidently thebio-based resin is performance competitive overall when compared to thecommercial control in β-hydroxy amide® crosslinked formulations.

Hybrid Powder Coatings: Carboxylic Acid-Epoxy Crosslinking

Carboxylic acid-epoxy crosslinked powder coatings are the most common ofthe hybrid coatings. Typically these are comprised of petroleum-derivedpolyester acids that are formulated with acrylic epoxy crosslinkers.Inventive carboxylic functional bio-based resins were synthesized andtested against the commercial petrochemical-based polyester acids intypical formulations.

FIG. 4A shows the comparative viscosity (in poise) versus shear rate at121° C. of a bio-based resin from this development versus a typicalcommercial resin (FINE-CLAD 8400) at 121° C. Note that the bio-basedresin (lower set of data points) is lower in viscosity than itscounterpart.

Based upon the viscosity difference, it is likely that the bio-basedmaterial will provide more flow at lower temperature, enabling anoverall improvement in appearance of low temperature cured coatings. Theimplication of the improvement can be approximately measured usingroughness average measurements from various industrial manufacturingmethods.

In Example 4A, the surface roughness (R_(a)) for the petrochemical basedcontrol clear coat is rated at 4.2, versus the bio-based clear coatrating of 1.3. The roughness of the petroleum derived panel wasequivalent to a typical sawing operation while the bio-based panel wasequivalent to a typical electron beam or laser operation. The bio-basedformulation is much closer to a “Class A” finish than the control.

Comparative panels of the Example 4A bio-based powder coating and acommercially available petroleum-derived low temperature cure powdercoating (Forrest Powder Low Temperature Cure®) were made. Both panelswere sprayed at approximately 2.5 mils film thickness then thermallycured for 30 minutes at 121° C. The bio-based powder material exhibitedconsiderably less orange peel (or surface roughness) than thecomparative powder coating. In addition, the bio-based powder coatedpanel exhibited a much higher gloss at 60° C. (72 points versus 50points). See Example 4A for the details of the formulation.

The improved melt flow of the bio derived formulation was measured witha stress-controlled rheometer. The samples of powder were placed betweenplatens heated to 100° C. and compressed to the thickness of a typicalpowder coating film (about 2 mils). The temperature is increased to 121°C. and the changes in viscosity are measured (in Poise) until the samplecured. The is viscosity data is shown in FIG. 5.

The upper curve data points indicate the comparative control powdersample and the lower curve data points indicate the bio-based powdersample. The initial viscosity of the bio-based formulation wassignificantly lower than the control sample (3694 Poise versus 11980Poise). As time passes both samples increased in viscosity as the samplecured. Because the viscosity of the bio-based formulation remained lowerfor the remainder of the cure time, the powder had more of anopportunity to melt and flow out before the film crosslinked and cured.

Flexibility (a measure of toughness) is a key coating attribute whichallows the end product to withstand the everyday bumps and dings thatcome with use of the coated object. Poor flexibility results in crackingof the coating and sometimes delamination from the substrate when animpact occurs. When the substrate is used outdoors, water, ultravioletradiation, oxidation and chemicals in the atmosphere, such as acid rain,can degrade and embrittle the film. Many of these factors alsocontribute to corrosion, which leads to rust and poor appearance loss aswell as poor flexibility.

The control sample and the bio-based formulation discussed immediatelyabove were compared in a flexibility test called the Mandrel Bend (ASTMD522). For this test, the coated substrates were clamped into a vise androlled over a conical mandrel. A tape adhesion test over the areadetermined the final performance of the coating. The tape is applied tothe bend area over the coating and is pulled off to determine if thecoating is still adhered to the panel.

The conical mandrel had varying widths across its length, down to 3.18mm (⅛ inch)—the smallest size available for testing and the toughest oneto pass without coating delamination or cracking.

The bio-based coating had good flexibility, as only minor cracking andno signs of delamination were evident. The control petroleum derivedcoating cracked through the length of the panels and the coatingdelaminated for approximately 40% of the length of the bend. See Example5 for formulation details.

Pigmented powder coatings may also derive some advantages from thebio-based resin formulations if the low viscosity at temperature iscomplimented by good wetting of the pigment surfaces. In Example 6, twoblack formulations, one control and one bio-based are described.

The bio-based powder coating had a much higher gloss at 60° C. than thepetrochemical-derived coating (85 points versus 44 points). This wasagain likely due to the better melt-flow of the formulation duringthermal cure.

The color development/jetness of the black pigment was improved with thebio-based formulation. Jetness can be determined by measuring the L andb color components of the coating. (For an explanation of the HunterColor Scale, see “Organic Coatings: Science and Technology”, SecondEdition, Wicks, Z. W. et al., especially pages 351-355, WileyInterscience, NY, N.Y. ISBN 0-471-24507-0 1999).

The overall Delta E, or color difference for the two black panels was0.52 with the bio-based being the more developed (jet). The controlpanel (left) appeared greyer than the bio-based formulation because theblack pigment was not dispersed as well into the coating system as thebio-based formulation. This is likely due to the low viscosity of thebio-based resin.

Referring now to FIG. 6, this figure is a schematic drawing showing thevarious elements of the apparatus 100 used for making resins accordingto the invention. A heating mantle 102 surrounds reactor 101 at least inpart and is used to control the temperature of reactor 101 containingreaction mixture 104. Reactor 101 consists of a reaction vessel 106 andtop 108. Top 108 has multiple necks 110, 112, 114, 116 for connection tovarious appliances. Stirring is provided by paddle 120 (e.g. typically45° angle blades) that is at the end of stirshaft 122 (e.g. stainlesssteel). Stirshaft 122 passes through neck 116. A thermocouple controller130 connected to thermocouple 132 via connector 131 passes through neck110 at gas inlet connector 111 in a sealed arrangement into reactionmixture 104. Vigreaux column 140 is mounted on neck 114 in sealedrelationship. A thermometer 141 or other temperature measuring device ismounted at the top (distillation head) 142 of the Vigreaux column 140.Condenser 150 is mounted to the Vigreaux column 140 at neck 144 withconnector 146 via condenser inlet 152. Vigreaux column 140 may be aseparate unit surrounded by a jacket or the jacket and column may beunitary. Condenser outlet 154 is connected at neck inlet 162 of neck 160that has a gas exit outlet 164, and neck outlet 166. Receiver flask 170has an inlet 172 connected to neck outlet 166. Cooling liquid 155 enterscondenser 150 at inlet 156 and exits at outlet 158.

In operation, argon gas 111-1 enters at gas inlet connector 111 toblanket reaction mixture 104 and flows out at gas exit 164. Ingredientscan be added before the apparatus is closed or through sealed connector118 at neck 112. Note that in FIG. 6, neck 112 is located directlybehind neck 116. Neck 112 is located on the central axis 190 of reactor101. Distillate 178 is collected in receiver flask 170.

The following examples are meant to be illustrative of various aspectsof the invention and are not meant to limit the scope of the inventionin any way.

RESIN PRODUCTION Example 1 through Example 3F Example 1

This example illustrates the production of a hydroxyl functionalbio-based polyester resin.

Equipment (see FIG. 6)

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask. Procedure

The reactor was charged with dimethyl terephthalate (DMT) (228.30 g,1.1757 moles), Speziol C36/2 1075® dimer diol (Batch #415252) (77.61 g,0.1411 moles), D-isosorbide (123.90 g, 0.84785 moles), and ethyleneglycol (EG) (102.81, 1.6563 moles), followed by manganese (II) acetatetetrahydrate (0.0917 g), cobalt (II) acetate tetrahydrate (0.0618 g),and antimony (III) oxide (0.103 g). The reactor was blanketed withargon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 30 minute period (1.6° C./min). Thistemperature was maintained for 30 minutes or until the temperaturedropped at the top of the Vigreaux column to 30° C. or less. Methanolwas continuously collected as the reaction was heated aboveapproximately 150° C. When the temperature drops at the top of theVigreaux column, this indicates that the methanol has been removed.Approximately 95 ml of methanol was distilled over. Subsequently, asolution of polyphosphoric acid (0.0634 g) in EG (1 g) was added to thereaction mixture. The argon flow rate over the reaction mixture waschecked and when necessary, reduced to a slow rate in order to avoiddistilling over isosorbide. The reaction mixture was slowly heated to280° C. over 2 hour period (0.25° C./min). The distillate receiver wasreplaced with the vacuum receiver and vacuum was gradually applied (<1Torr). During this time, ethylene glycol distilled off (91 g), and a lowmolecular weight polymer formed. The reaction mixture temperature wasmaintained at 280° C. for 3 hours and 10 minutes. The reaction wasterminated by blanketing the reaction mixture with argon to obtainatmospheric pressure. The reaction mixture was then cooled to ≦250° C.and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:

Solution inherent viscosity: 0.29 (solvent is o-chlorophenol, only 92%soluble)

T_(g)=61° C. Hydroxyl Value=24.3 Acid Value=8.0

Molecular Weight (MW)=3470 (Calculated from acid and hydroxyl values)

Polymer Characteristics: Color: Brown Tackiness: Non-tacky

Clarity: Slightly translucent

Flexibility: Brittle Solid Example 1A

This example illustrates the production of a bio-based polyester resin.Equipment (see FIG. 6)

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with dimethyl terephthalate (DMT) (197.74 g,1.0183 moles), D-isosorbide (119.05 g, 0.81463 moles), and Speziol C36/21075® dimer diol (Batch #415252) (112.06 g, 0.20371 moles), followed by1,2,3,4-tetrahydronaphthalene (2 ml) and antimony (III) oxide (0.089 g).The reactor was blanketed with argon. The temperature of the reactorcontents was raised to 200° C. with stirring (after solids melted) underargon. This temperature was maintained for 12 minutes. The reactionmixture was slowly heated to 250° C. over a 20 minute period (2.5°C./min). This temperature was maintained for 8 minutes. Methanol wascontinuously collected as the reaction was heated above approximately150° C. When the temperature drops at the top of the Vigreaux column,this indicates that the methanol has been removed. Approximately 83 mlof methanol was distilled over. The argon flow rate over the reactionmixture was checked and when necessary, reduced to a slow rate in orderto avoid distilling over isosorbide. The reaction mixture was slowlyheated to 280° C. over 13 minute period (2.3° C./min). Then, thereaction mixture was allowed to cool to 260° C. Additional D-isosorbide(14.87 g, 0.1018 moles) was charged to the reaction mixture. Thereaction mixture was heated to 280°. This temperature was maintained for30 minutes. The distillate receiver was replaced with the vacuumreceiver and vacuum was gradually applied (≦9 Torr). During this time, alow molecular weight polymer formed. The reaction mixture temperaturewas maintained at 280° C. for 2 hours and 40 minutes. The reaction wasterminated by blanketing the reaction mixture with argon to obtainatmospheric pressure. The reaction mixture was then cooled to ≦250° C.and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:Solution inherent viscosity: 0.10 (solvent is o-chlorophenol)

T_(g)=165° C. Hydroxyl Value=45.0 Acid Value=2.3

Molecular Weight (MW)=2372 (Calculated from acid and hydroxyl values)

Polymer Characteristics: Color: Light Brown Tackiness: Tacky Clarity:Translucent Flexibility: Somewhat Brittle Solid Example 2

This example illustrates the production of a carboxyl functionalbio-based polyester resin.

Equipment (see FIG. 6).

5 liter round bottom glass reaction vessel with 4 neck top, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with D-isosorbide (1337.0 g, 9.1490 moles) (asreceived), Pripol 1013® dimer acid (batch #091687) (699.1 g, 1.215moles), and 1,4-cyclohexanedicarboxylic acid (1,4-CHDA) (1563.8 g,9.0826 moles) followed by antimony (III) oxide (1.231 g). The reactorwas blanketed with argon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) wasadded to the reaction mixture under argon. The temperature of thereactor contents was raised to 200° C. with stirring (after solidsmelted) under argon. This temperature was maintained for 30 minutes. Thereaction mixture was slowly heated to 250° C. over a 47 minute period(1.1° C./min). This temperature was maintained for 3.1 hours or untilthe temperature dropped at the top of the Vigreaux column to 30° C. orless. Water was continuously collected as the reaction was heated aboveapproximately 180° C. When the temperature drops at the top of theVigreaux column, this indicates that most of the water has been removed.Approximately 329 ml of water distilled over. The argon flow rate overthe reaction mixture was checked and when necessary, reduced to a slowrate in order to avoid distilling over isosorbide. The reaction mixturewas slowly heated to 280° C. over a 2 hour period (0.25° C./min). Thedistillate receiver was replaced with the vacuum receiver and vacuum wasgradually applied (<1 Torr). During this time, residual water distilledover, and a low molecular weight polymer formed. The reaction mixturetemperature was maintained at 280° C. for 3 hours and 10 minutes. Thereaction was terminated by blanketing the reaction mixture with argon toobtain atmospheric pressure. The reaction mixture was then cooled to≦250° C. and poured onto a fluorinated fiber glass sheet.

A resin was produced with the following properties:

T_(g)=64.2° C. Acid Value=34.8 Molecular Weight (MW)

GPC (polystyrene standard) M_(n)=1689

GPC (polystyrene standard) M_(w)=11681

Polydispersity (M_(w)/M_(n))=6.91

Polymer Characteristics: Color: Light Amber Tackiness: Non TackyClarity: Translucent Flexibility: Brittle Solid Example 3

This example illustrates the production of a carboxyl functionalbio-based polyester resin.

Equipment (see FIG. 6).

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with 1,4-cyclohexanedicarboxylic acid (1,4-CHDA)(204.66 g, 1.1886 moles), Empol 1018® dimer acid (batch # U42G151910)(72.54 g, 0.1251 moles), and D-isosorbide (172.80 g, 1.1824 moles)followed by antimony (III) oxide (0.1594 g) The reactor was blanketedwith argon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 30 minute period (1.6° C./min). Thistemperature was maintained for 30 minutes or until the temperaturedropped at the top of the Vigreaux column to 30° C. or less. Water wascontinuously collected as the reaction was heated above approximately180° C. When the temperature drops at the top of the Vigreaux column,this indicates that most of the water has been removed. Approximately 47ml of water distilled over. The argon flow rate over the reactionmixture was checked and when necessary, reduced to a slow rate in orderto avoid distilling over isosorbide. The reaction mixture was slowlyheated to 280° C. over 2 hour period (0.25° C./min). The distillatereceiver was replaced with the vacuum receiver and vacuum was graduallyapplied (<1 Torr). During this time, residual water distilled off and alow molecular weight polymer formed. The reaction mixture temperaturewas maintained at 280° C. for 3 hours and 10 minutes. The reaction wasterminated by blanketing the reaction mixture with argon to obtainatmospheric pressure. The reaction mixture was then cooled to ≦250° C.and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:Solution inherent viscosity=0.25 dl/g (solvent is o-chlorophenol):

T_(g)=66.9° C. Hydroxyl Value=13.0 Acid Value=36.3 Molecular Weight (MW)

GPC (polystyrene standard) M_(n)=2995

GPC (polystyrene standard) M_(w)=9560

Polydispersity (M_(w)/M_(n))=3.19

Polymer Characteristics: Color: Light Brown Tackiness: Non-tackyClarity: Mostly Translucent

Flexibility: Brittle but hard.

Solid Example 3A

This example illustrates the production of a carboxyl functionalbio-based polyester resin.

Equipment (see FIG. 6)

5 liter round bottom glass reaction vessel with 4 neck top, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with 1,4-cyclohexanedicarboxylic acid (1,4-CHDA)(1570.3 g, 9.1202 moles), Pripol 1013® dimer acid (batch #091687) (675.7g, 1.174 moles), D-isosorbide (as received) (1354.0 g, 9.2648 moles),followed by antimony (III) oxide (1.247 g). The reactor was blanketedwith argon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 51 minute period (1.0° C./min). Thistemperature was maintained for 3.1 hours or until the temperaturedropped at the top of the Vigreaux column to 30° C. or less. Water wascontinuously collected as the reaction was heated above approximately180° C. When the temperature drops at the top of the Vigreaux column,this indicates that most of the water has been removed. Approximately334 ml of water was distilled over. The argon flow rate over thereaction mixture was checked and when necessary, reduced to a slow ratein order to avoid distilling over isosorbide. The reaction mixture wasslowly heated to 280° C. over 2 hour period (0.25° C./min). Thedistillate receiver was replaced with the vacuum receiver and vacuum wasgradually applied (<1 Torr). During this time, residual water distilledoff, and a low molecular weight polymer formed. The reaction mixturetemperature was maintained at 280° C. for 3 hours and 10 minutes. Thereaction was terminated by blanketing the reaction mixture with argon toobtain atmospheric pressure. The reaction mixture was then cooled to≦250° C. and poured onto a fluorinated fiber glass sheet.

A resin was produced with the following properties:

T_(g)=65.3 Acid Value=29.0 Molecular Weight (MW)

GPC (polystyrene standard) M_(n)=2162

GPC (polystyrene standard) M_(w)=11872

Polydispersity (M_(w)/M_(n))=5.49

Polymer Characteristics: Color: Yellow/Light Amber Tackiness: Non-TackyClarity: Translucent Flexibility: Brittle Solid Example 3B

This example illustrates the production of a hydroxyl functionalbio-based polyester resin.

Equipment (see FIG. 6)

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with dimethyl terephthalate (DMT) (228.30 g,1.1757 moles), Speziol C36/2 1075® dimer diol (Batch #415252) (129.40 g,0.23523 moles), D-isosorbide (123.90 g, 0.84785 moles), and ethyleneglycol (EG) (89.66 g, 1.444 moles), followed by manganese (II) acetatetetrahydrate (0.0917 g), cobalt (II) acetate tetrahydrate (0.0618 g),and antimony (III) oxide (0.103 g). The reactor was blanketed withargon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 30 minute period (1.6° C./min). Thistemperature was maintained for 30 minutes or until the temperaturedropped at the top of the Vigreaux column to 30° C. or less. Methanolwas continuously collected as the reaction was heated aboveapproximately 150° C. When the temperature drops at the top of theVigreaux column, this indicates that the methanol has been removed.Approximately 95 ml of methanol was distilled over. Subsequently, asolution of polyphosphoric acid (0.0634 g) in EG (1 g) was added to thereaction mixture. The argon flow rate over the reaction mixture waschecked and when necessary, reduced to a slow rate in order to avoiddistilling over isosorbide. The reaction mixture was slowly heated to280° C. over a 30 minute period (1° C./min). The distillate receiver wasreplaced with the vacuum receiver and vacuum was gradually applied (<1Torr). During this time, ethylene glycol distilled off (84 g), and a lowmolecular weight polymer formed. The reaction mixture temperature wasmaintained at 280° C. for 3 hours and 10 minutes. The reaction wasterminated by blanketing the reaction mixture with argon to obtainatmospheric pressure. The reaction mixture was then cooled to ≦250° C.and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:Solution inherent viscosity: 0.19 (solvent is o-chlorophenol)

T_(g)=28.4° C. Hydroxyl Value=35.4 Acid Value=6.1

Molecular Weight (MW)=2700 (Calculated from add and hydroxyl values)

Polymer Characteristics: Color: Brown Tackiness: Non-tacky

Clarity: Mostly translucent

Flexibility: Brittle Solid Example 3C

This example illustrates the production of a hydroxyl functionalbio-based polyester resin.

Equipment (see FIG. 6)

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with dimethyl terephthalate (DMT) (213.96 g,1.1018 moles), Empol 1018® dimer acid (Batch # U42G151910) (71.02 g,0.1225 moles), D-isosorbide (128.79 g, 0.88128 moles), and ethyleneglycol (EG) (116.28 g, 1.8734 moles), followed by manganese (II) acetatetetrahydrate (0.0859 g), cobalt (II) acetate tetrahydrate (0.0579 g),and antimony (III) oxide (0.0965 g). The reactor was blanketed withargon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 30 minute period (1.6° C./min). Thistemperature was maintained for 30 minutes or until the temperaturedropped at the top of the Vigreaux column to 30° C. or less. Methanolwas continuously collected as the reaction was heated aboveapproximately 150° C. When the temperature drops at the top of theVigreaux column, this indicates that the methanol/water mixture has beenremoved. Approximately 93 ml of methanol/water mixture was distilledover. Subsequently, a solution of polyphosphoric acid (0.0594 g) in EG(1 g) was added to the reaction mixture. The argon flow rate over thereaction mixture was checked and when necessary, reduced to a slow ratein order to avoid distilling over isosorbide. The reaction mixture wasslowly heated to 280° C. over 2 hour period (0.25° C./min). Thedistillate receiver was replaced with the vacuum receiver and vacuum wasgradually applied (<1 Torr). During this time, ethylene glycol distilledoff (95 g), and a low molecular weight polymer formed. The reactionmixture temperature was maintained at 280° C. for 3 hours and 10minutes. The reaction was terminated by blanketing the reaction mixturewith argon to obtain atmospheric pressure. The reaction mixture was thencooled to ≦250° C. and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:Solution inherent viscosity: 0.23 (solvent is o-chlorophenol)

T_(g)=58.8° C. Hydroxyl Value=23.7 Acid Value=1.4

Molecular Weight (MW)=4470 (Calculated from acid and hydroxyl values)

Polymer Characteristics: Color: Light Brown Tackiness: Non-tacky

Clarity: Somewhat translucent, slight haze

Flexibility: Brittle Solid Example 3D

This example illustrates the production of a carboxyl functionalbio-based polyester resin.

Equipment (see FIG. 6)

2 liter 4-neck cylindrical walled round bottom glass reaction vessel,jacketed Vigreaux column, distillation head, gas inlet and exitadapters, stainless steel stir shaft and four blade (45° angle) paddle,condenser, and receiver flask.

Procedure

The reactor was charged with 1,4-cyclohexanedicarboxylic acid (1,4-CHDA)(610.68 g, 3.5468 moles), Pripol 1013® dimer acid (batch #091687)(262.78 g, 0.45670 moles), D-isosorbide (re-crystallized with acetone)(526.54 g, 3.6030 moles), followed by antimony (III) oxide (0.4849 g).The reactor was blanketed with argon. Then,1,2,3,4-tetrahydronaphthalene (2 ml) was added to the reaction mixtureunder argon. The temperature of the reactor contents was raised to 200°C. with stirring (after solids melted) under argon. This temperature wasmaintained for 30 minutes. The reaction mixture was slowly heated to250° C. over a 30 minute period (1.6° C./min). This temperature wasmaintained for 2.1 hours. Water was continuously collected as thereaction was heated above approximately 180° C. When the temperaturedrops at the top of the Vigreaux column, this indicates that most of thewater has been removed. Approximately 129 ml of water was distilledover. The argon flow rate over the reaction mixture was checked and whennecessary, reduced to a slow rate in order to avoid distilling overisosorbide. The reaction mixture was slowly heated to 280° C. over 2hour period (0.25° C./min). The distillate receiver was replaced withthe vacuum receiver and vacuum was gradually applied (<1 Torr). Duringthis time, residual water distilled off, and a low is molecular weightpolymer formed. The reaction mixture temperature was maintained at 280°C. for 3 hours and 10 minutes. The reaction was terminated by blanketingthe reaction mixture with argon to obtain atmospheric pressure. Thereaction mixture was then cooled to ≦250° C. and poured onto afluorinated fiber glass sheet.

A resin was produced with the following properties:

T_(g)=62.3 Acid Value=34.7 Molecular Weight (MW)

GPC (polystyrene standard) M_(n)=3517

GPC (polystyrene standard) M_(w)=12753

Polydispersity (M_(w)/M_(n))=3.63

Polymer Characteristics: Color: Amber/Orange Tackiness: Non-TackyClarity: Translucent Flexibility: Brittle Solid Example 3E

This example illustrates the production of a carboxyl functionalbio-based polyester resin.

Equipment (see FIG. 6).

1 liter 4-neck cylindrical walled round bottom glass flask, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with 1,4-cyclohexanedicarboxylic acid (1,4-CHDA)(318.36 g, 1.8490 moles), Empol 1018® dimer acid (batch # U42G151910)(112.84 g, 0.1946 moles), and D-isosorbide (268.80 g, 1.8393 moles)followed by antimony (III) oxide (0.2479 g) The reactor was blanketedwith argon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) was added to thereaction mixture under argon. The temperature of the reactor contentswas raised to 200° C. with stirring (after solids melted) under argon.This temperature was maintained for 30 minutes. The reaction mixture wasslowly heated to 250° C. over a 30 minute period (1.6° C./min). Thistemperature was maintained for 2.3 hours. Water was continuouslycollected as the reaction was heated above approximately 180° C. Whenthe temperature drops at the top of the Vigreaux column, this indicatesthat most of the water has been removed. Approximately 74 ml of waterdistilled over. The argon flow rate over the reaction mixture waschecked and when necessary, reduced to a slow rate in order to avoiddistilling over isosorbide. The reaction mixture was slowly heated to280° C. over 2 hour period (0.25° C./min). The distillate receiver wasreplaced with the vacuum receiver and vacuum was gradually applied (<1Torr). During this time, residual water distilled off and a lowmolecular weight polymer formed. The reaction mixture temperature wasmaintained at 280° C. for 3 hours and 10 minutes. The reaction wasterminated by blanketing the reaction mixture with argon to obtainatmospheric pressure. The reaction mixture was then cooled to ≦250° C.and poured onto a fluorinated fiber glass sheet.

A resin was produced having the following properties:

Solution inherent viscosity=0.24 dl/g (solvent is o-chlorophenol):

T_(g)=72.3° C. Hydroxyl Value=0.0 Acid Value=32.8 Molecular Weight (MW)

GPC (polystyrene standard) M_(n)=4027

GPC (polystyrene standard) M_(w)=15756

Polydispersity (M_(w)/M_(n))=3.91

Polymer Characteristics: Color: Yellow-Brown Tackiness: Non-tackyClarity: Mostly Translucent Flexibility: Brittle Solid

The following examples 4 through 8 illustrate several typical powderformulations and finished coatings according to the invention.

Example 3F Pigment Dispersion Agent

This example illustrates the production of a carboxyl functionalbio-based polyester resin having improved dispersant properties whenused in the presence of a pigment.

Equipment (see FIG. 6).

2 liter round bottom glass reaction vessel with 4 neck top, jacketedVigreaux column, distillation head, gas inlet and exit adapters,stainless steel stir shaft and four blade (45° angle) paddle, condenser,and receiver flask.

Procedure

The reactor was charged with D-isosorbide (545.35 g, 3.7317 moles) (asreceived), Pripol 1013® dimer acid (batch #091687) (272.17 g, 0.47302moles), and 1,4-cyclohexanedicarboxylic acid (1,4-CHDA) (63249 g, 3.6734moles) followed by antimony (III) oxide (0.498 g). The reactor wasblanketed with argon. Then, 1,2,3,4-tetrahydronaphthalene (2 ml) wasadded to the reaction mixture under argon. The temperature of thereactor contents was raised to 200° C. with stirring (after solidsmelted) under argon. This temperature was maintained for 30 minutes. Thereaction mixture was slowly heated to 250° C. over a 30 minute period(1.6° C./min). This temperature was maintained for 2.1 hours. Water wascontinuously collected as the reaction was heated above approximately180° C. When the temperature drops at the top of the Vigreaux column,this indicates that most of the water has been removed. Approximately134 ml of water distilled over. The argon flow rate over the reactionmixture was checked and when necessary, reduced to a slow rate in orderto avoid distilling over isosorbide. The reaction mixture was slowlyheated to 280° C. over a two hour period (0.25° C./min). The distillatereceiver was replaced with the vacuum receiver and vacuum was graduallyapplied (<1 Torr). During this time, residual water distilled over, anda low molecular weight polymer formed. The reaction mixture temperaturewas maintained at 280° C. for 30 minutes. The reaction was terminated byblanketing the reaction mixture with argon to obtain atmosphericpressure. The reaction mixture was then cooled to ≦250° C. and pouredonto a fluorinated fiber glass sheet.

A resin was produced with the following properties:

T_(g)=52.9° C. Acid Value=47.7 Viscosity at 120° C.=7772 Poise Viscosityat 160° C.=247 Poise Polymer Characteristics: Color: Yellow/Light AmberTackiness: Non Tacky Clarity: Translucent Flexibility: Brittle SolidExample 4

This example illustrates the preparation of a powder coating formulationusing carboxyl functional resins polyester resins from Example 3 with(3-hydroxy amide type crosslinking. The powder formulation is thenapplied to a substrate.

The carboxyl functional polyester (product of Example 3) was compared toa commercial polyester in a side-by-side comparison of a typical powdercoating formulation compounded as described above and crosslinked by(3-hydroxy amide transesterification. Table 4 below shows theseformulations as a weight percentage.

TABLE 4 Formulations of a bio-based and a commercial carboxyl functionalpolyester A B Type Code (wt. %) (wt. %) COOH func. Example 3 product93.2 Bio-based polyester COOH func FINE-CLAD M8930 ® 93.2 Commercialpolyester Cross linker PRIMID XL 5526 ® 4.9 4.9 de-gas additive Benzoin1.3 1.3 flow promoter MODAFLOW 6000 0.6 0.6 Tg Acid (° C.) Value Example3 product 67 36.3 FINE-CLAD M8930 ® 65 35FINE-CLAD M8930® is an example of a polyester acid used for comparisonpurposesProcedure: Powder Coating Mix Protocol (99° C. mix in a Brabender®mixer):

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 grams total formulation weight. The Brabender® mixerwas preheated to 99° C. (bowl rose to about 99° C.). About 30 minuteswere allowed for preheating. When preheating was complete, the mixingblades were started and the torque sensor was turned on. This acted as aguide for how the mix was proceeding, then 30 g of primary resin wereslowly added to the bowl and mixed until melted; then the remaining 35.2g of primary resin was added. The resin was allowed to mix and meltuntil the torque sensor showed a steady value (about 5 minutes). Then1.3 g of additives (0.9 g of benzoin and 0.4 g of Modaflow 6000®) wereadded to center of mix zone between rotors;

Mixing continued for 10 minutes, (the torque value was monitored forstability); then 3.4 g of the crosslinking resin (Primid XL-552®) wasadded to the previous mixture; mixing continued for at least 3 minutes,the torque reading was monitored to make sure it remained stable in casecrosslinking started) (torque reading will start to rise rapidly); thetorque reading was monitored closely. The torque increased and the batchwas stopped after a 10% rise in viscosity (torque).

The product was removed from the mixing bowl as a smooth, firm, shinymaterial and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto 4 inch×6 inch bare steelpanels using a Versa-Spray® manual spray gun supplied by NordsonCorporation. The panels were cured for 30 minutes at either 121° C. or147° C. for 30 minutes (see Table 6 for test results).

The above procedure was repeated to obtain the control material.

The bio-based coating was far more robust in terms of gloss at varyingtemperatures, having equivalent gloss at the lower temperature and had afar better gloss at higher temperature.

Differential Scanning calorimetry (DSC) results showed that theexperimental resin did not affect the cure temperature, the magnitude ofthe cure, or the coating's final T_(g) in either a positive or negativesense. This was consistent with the insensitivity of β-hydroxy amidecure rates to external influence (see Howell reference).

TABLE 5 Cure thermodynamics of hybrid coatings compounded from inventiveversus commercial control resin T onset T peak Tg (tangent) of cure DSCResults (° C.) (° C.) (° C.) Delta H A - commercial 76.2 123.9 127.84.897 J/g control B - Bio-based 75.7 122.6 128   5.203 J/g (Example 1)

The bio-based coating also had final properties that were similar to thecommercial control at both curing temperatures:

TABLE 6 Film properties of test formulations Film Properties One weekhumidity storage Cure (100% humidity, Tem- Cross- 32° C.) per- PencilMEK hatch Crosshatch Test ature Hard- Double adhesion adhesionformulation (° C.) ness rubs (% Loss) Blush (% Loss) A-1 (comp) 121 HB10 50 yes 50 B-1 (bio) 121 B 10 50 yes 50 A-2 (comp) 147 3H 45 100 no100 B-2 (bio) 147 3H 20 100 no 100

The data in Tables 5 and 6 shows that both coatings are essentially isequivalent in overall performance. The bio-based coating had a slightadvantage in gloss at higher cure temperature, and the commercialcontrol had a small advantage in solvent resistance. As previouslystated, the gloss at higher temperature may be a significant advantagein formulations requiring great temperature robustness.

Thus, bio-based resins of this type are useful as transesterificationcrosslinking reactions with β-hydroxy alkylamides.

Example 4A

This example illustrates the preparation of a powder coating formulationusing carboxyl functional resins with β-hydroxy amide type crosslinking.

A carboxylic functional polyester (Example 3E) was compared to acommercial polyester in a side-by-side comparison of a typical powdercoating formulation compounded as described above and crosslinked byβ-hydroxy amide trans-esterification. Table 4A below shows theseformulations as a weight percentage.

TABLE 4A Formulations of a bio-based and a commercial carboxylfunctional polyester A B Type of Material Specific Material (wt. %) (wt.%) COOH func. Bio-based Example 3E product 91 polyester COOH func.Commercial FINE-CLAD M8930 ® 91 polyester cross linker PRIMID XL 552 ®4.8 4.8 de-gas additive Benzoin 1.3 1.3 flow promoter Fine Clad A241 ®2.9 2.9 Tg (° C.) Acid Value Example 3E product 72.3 32.8 FINE-CLADM8930 ® 65 35

First a total formulation weight was calculated based on a 120 ml bowlsize; or about 85 g total formulation weight. The Brabender® mixer waspreheated to 99° C. (bowl rose to about 99° C.). About 30 minutes wereallowed for preheating. When preheating was complete, the mixing bladeswere started and the torque sensor was turned on. This acted as a guidefor how the mix was proceeding; then 30 g of primary resin were slowlyadded to the bowl and mixed until melted; then the remaining 37.8 g ofprimary resin was added. The resin was allowed to mix and melt until thetorque sensor showed a steady value (about 5 minutes); then 3.6 g ofadditives (1.1 g of Benzoin and 2.5 g of Fine Clad A241®) were added tocenter of mix zone between rotors; mixing continued for 10 minutes, (thetorque value was monitored for stability); then 4.1 g of thecrosslinking resin (Primid XL-552®) was added to the previous mixture;mixing continued for at least 3 minutes, the torque reading wasmonitored to make sure it remained stable in case crosslinking started)(torque reading will start to rise rapidly); the torque reading wasmonitored closely. The torque increased and the batch was stopped aftera 10% rise in viscosity (torque). The product was removed from themixing bowl as a smooth, firm, shiny material and allowed to cool toroom temperature. The material was broken into small chips with ahammer. Finally the product was micronized in a ball mill in thepresence of 10 mm-15 mm steel media for 16 hours. A final powder wasobtained and sieved to remove any particles over 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation. The panels were cured for 30 minutes ateither 121° C. or 147° C. for 30 minutes (see Table 6 for test results).The above procedure for Example 4A was repeated to obtain the controlmaterial.

The bio-based coating was far more robust in terms of gloss at varyingtemperatures, having equivalent gloss at the lower temperature and had afar better gloss at higher temperature.

Differential Scanning calorimetry (DSC) results showed that theexperimental coating did not affect the cure temperature, the magnitudeof the cure, or the coating's final T_(g) in either a positive ornegative sense. This was consistent with the insensitivity of β-hydroxyamide cure rates to external influence (see Howell reference).

TABLE 5A Cure thermodynamics of hybrid coatings compounded frominventive versus commercial control resin T onset T peak Tg (tangent) ofcure DSC Results (° C.) (° C.) (° C.) Delta H 4A-A Control 72.8 About110 117.2 5.029 J/g 4A-B Bio-based 72.4 113.0 119.5 4.164 J/g (Example3E product)

The bio-based coating also had final properties that were similar to thecommercial control at both curing temperatures as seen in Table 6Abelow.

TABLE 6A Film properties of test formulations Film Properties CurePencil MEK Crosshatch Test Temperature Hardness Double adhesionformulation (° C.) (#) rubs (% Loss) 60° Gloss 4A-A-1 con 121 HB 10 10095.8 4A-B-1 bio 121 3H 5 10 93.4 4A-A-2 con 147 3H 80 0 59.3 4A-B-2 bio147 4H 14 0 97.0

The data in Tables 5A and 6A show that both coatings are essentiallyequivalent in overall performance. The bio-based had the advantage of aharder film at the lower cure temperature—#H pencil versus #HB pencil.The bio-based also had an advantage in gloss at higher cure temperature,and the commercial control had a advantage in solvent resistance. Aspreviously stated, the gloss at higher temperature may be a significantadvantage in formulations requiring great temperature robustness.

Thus, bio-based resins of this type are useful as transesterificationcrosslinking reactions with β-hydroxy alkylamides.

Example 5

This example illustrates the preparation of formulation for a hybridcoating formulated with a carboxyl functional polyester resin (productfrom Example 2) and an acrylic epoxy cross linker.

Procedure: Powder Coating Mix Protocol for Bio-based Hybrid PowderCoating (99° C. mix in Brabender® mixer):

First a total formulation weight was calculated based on 120 ml bowlsize; or approximately 70 g of total formulation weight. The Brabender®mixer was preheated to 99° C. (bowl rose to about 99° C.). About 30minutes were allowed for preheating. When preheating was complete, themixing blades were started and the torque sensor was turned on. Thisacted as a guide for how the mix was proceeding. Then 30 g of primaryresin (resin described in Example 2) were slowly added to the bowl andmixed until melted; the remaining 21.5 g of primary resin was added. Theresin was allowed to mix and melt until the torque sensor showed asteady value (about 5 minutes); Mixing continued for 10 minutes, (thetorque value was monitored for stability); 16.9 g of crosslinking resin(Fine Clad A229-30A®) was added to the previous mixture; mixingcontinued for at least 3 minutes, the torque reading was monitored tomake sure it remained stable in case crosslinking started) (torquereading will start to rise rapidly); the torque reading was monitoredclosely. The catalyst was ground to a fine powder and was added last(0.4 g of imidazole and 1.1 g of dodecanedioic acid). The torqueincreased and the batch was stopped after a 10% rise in viscosity(torque).

The product was removed from the mixing bowl as a smooth, firm, shinymaterial and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to approximately 2.5 mils dry filmthickness. The panels were cured for 30 minutes at 121° C. for 30minutes.

Procedure: Powder coating mix protocol for control polyester hybridpowder coating (99° C. mix in Brabender® mixer):

First a total formulation weight was calculated based on 120 ml bowlsize; or approximately 70 g of total formulation weight. The Brabender®mixer was preheated to 99° C. (bowl rose to about 99° C.). 30 minuteswere allowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30 g of primary resin (Fine-Clad M8400) were slowlyadded to the bowl and mixed until melted; the remaining 25.8 g ofprimary resin was added. The resin was allowed to mix and melt until thetorque sensor showed a steady value (about 5 minutes); mixing continuedfor 10 minutes, (the torque value was monitored for stability); 12.7 gof crosslinking resin (Fine Clad A229-30A®) was added to the previousmixture; mixing continued for at least 3 minutes, the torque reading wasmonitored to make sure it remained stable in case crosslinking started)(torque reading will start to rise rapidly); the torque reading wasmonitored closely. The catalyst (0.4 g of imidazole and 1.1 g ofdodecanedioic acid) was added last, watching the torque reading closely.The torque increased and the batch was stopped after a 10% rise inviscosity (torque).

The product was removed from the mixing bowl as a smooth, firm, shinymaterial and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to approximately 2.5 mils dry filmthickness. The panels were cured for 30 minutes at 121° C. for 30minutes.

The two polyester resins described in this example have viscositieswhich were described in FIG. 4 were formulated into clear coats perthese procedures and are shown below in Table 7. Table 7 shows theamounts of various ingredients in weight percentages.

TABLE 7 Formulations of a bio-based and a commercial carboxyl functionalpolyester A B Type of Material Specific Material (wt. %) (wt. %) COOHfunc. Bio-based Example 2 product 73.6 polyester COOH func ControlFINE-CLAD M8400 ® 79.7 polyester Epoxy Crosslinker FINE-CLAD 18.1 24.2A229-30A ® Catalyst Imidazole 0.6 0.6 Cure modifier Dodecanedioic acid1.6 1.6

A comparison was made of the effect of cure on appearance, for thebio-based material and a control system. A low cure temperature powdercoating was selected as control. The product tested is designated1PC-306-0040 (F-0040) S-9 Clear Gloss®. The cure schedule was 15 minutesat 145° C. or 10 minutes at 162° C.

Surface roughness of the coatings was quantified by a profilometer.During this test a thin needle passed over the surface of the coatingwhile the peaks and valleys of the surface were recorded. The valleyswere recorded as R_(v) (nm) and the peaks were recorded as R_(p) (nm).An average roughness (R_(a)) is calculated from these two values. LowerR values indicate a surface that is more level or smooth. See Table 8for the R values for the coated panels.

TABLE 8 Surface Roughness R_(a) Value (μm) R_(v) Value (μm) R_(p) Value(μm) Bio-based 1.34  5.11  4.04 Petroleum-derived 4.22 12.62 15.70control

Typical R values for surface roughness produced by common productionsmethods (as listed in ASME B46.1-1995) can be compared to the values inTable 8. The surface roughness of the bio-based panel is similar to thesurfaces produced by grinding, honing and electro-polishing. The surfaceroughness of the control panel is similar to the surfaces produced bysnagging, planing and shaping operations.

Example 6

This example illustrates a pigmented hybrid powder coating formulatedfrom with a bio-based carboxyl functional polyester of Example 3A and anepoxy crosslinker.

Pigmented powder coatings may also benefit if the bio-based resin hassuperior ability to disperse and develop the color of the pigment. Anexample of a black powder coating formulation (below), was made upversus a commercial control, see Table 9. The formulations in Table 9show the amounts of various ingredients based on a weight percentage.

TABLE 9 Formulations of bio-based and commercial carboxyl functionalpolyester black powder coatings A B Type of Material Specific Ingredient(wt. %) (wt. %) COOH func. Bio-based polyester (Example 3A product) 75.9COOH functional Control FINE-CLAD M8400 ® 74.2 polyester Epoxyfunctional Control acrylic FINE-CLAD A257 ® 17.9 16.2 Carbon blackpigment Black 1300 ® (Cabot) 1.1 1.1 De-gas additive Benzoin 1.3 1.3Catalyst Imidazole 0.7 0.7 Diacid cure modifier Dodecanedioic acid 2.42.4 Acidic cure modifier NACURE 7231 ® 2.4 2.4

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g total formulation weight. The Brabender® mixer waspreheated to 99° C. (bowl rose to about 99° C.). 30 minutes were allowedfor preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30 g of primary resin (as described in Example 3A) wereslowly added to the bowl; allowed to mix until melted and the remaining23.1 g of resin was added. The resin was allowed to mix and melt untilthe torque sensor showed a steady value (about 5 minutes); 1.7 g ofadditives (0.8 g of black pigment and 0.9 g of benzoin) were added tocenter of mix zone between rotors;

Mixing continued for 10 minutes, (the torque value was monitored forstability); is The 11.3 g of crosslinking resin, an acrylic with epoxyfunctional groups, (FineClad A257®) was added to the previous mixture;mixing continued for at least 3 minutes, the torque reading wasmonitored to make sure it remained stable in case crosslinking started)(torque reading will start to rise rapidly); the torque reading wasmonitored closely. The catalyst was ground to a fine powder and addedlast (0.5 g of imidazole, 1.7 g of dodecanedioic acid and 1.7 g ofNacure XC-7231®). The torque increased and the batch was stopped after a10% rise in viscosity (torque).

The product was removed from the mixing bowl as a black smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C. for 30 minutes.

For the control polyester pigmented powder coating, a total formulationweight was calculated based on 120 ml bowl size; or about 70 g totalformulation weight. The Brabender® mixer was preheated to 99° C. (bowlrose to about 99° C.). About 30 minutes were allowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30 g of primary resin (Fine-Clad M8400®) were slowlyadded to the bowl; allowed to mix until melted and the remaining 21.9 gof resin was added. The resin was allowed to mix and melt until thetorque sensor showed a steady value (about 5 minutes); 1.7 g ofadditives (0.8 g of Black pigment and 0.9 g of benzoin) were added tocenter of mix zone between rotors. Mixing continued for 10 minutes, (thetorque value was monitored for stability). The 12.5 g of crosslinkingresin (FineClad A257®) was added to the previous mixture; mixingcontinued for at least 3 minutes, the torque reading was monitored tomake sure it remained stable in case crosslinking started) (torquereading will start to rise rapidly); the torque reading was monitoredclosely. The catalyst (0.5 g of imidazole, 1.7 g of dodecanedioic acidand 1.7 g of Nacure XC-7231®) was added last, watching the torquereading closely. The torque increased and the batch was stopped after a10% rise in viscosity (torque).

The product was removed from the mixing bowl as a black smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C. for 30 minutes.

The bio-based powder coating had a much higher 60° gloss than thepetrochemical-derived coating (85 points versus 44 points). This waslikely due to the better melt-flow of the formulation during thermalcure.

The color development/jetness of the black pigment is improved with thebio-based formulation. Jetness can be determined by measuring the L andb color components of the coating. (For an explanation of the Huntercolor Scale see Wicks, Z. W. et al. cited above).

Extreme black is determined by low L values and deep blue undertones aredetermined by low b values. The lower the L and b values, the more jetthe coating. The jetness is improved with better pigment dispersion andcolor development. Table 10 below shows the color measurements from thecoated panels:

TABLE 10 Color Data Test Panel L value b value Bio-based 24.53 −0.38Petroleum-derived 25.06 −0.27

The overall Delta E, or color difference for the two black panels is0.52. The petroleum derived panel appears greyer than that of thebio-based formulation because the black pigment was not dispersed aswell into the coating system as the bio-based formulation.

Example 6A

In addition to the need for low temperature flow and cure in powdercoatings, there is also a need for good dispersion of pigments within acoating matrix, regardless of the coating type. To accomplish this,polymers are designed that have components with differingcompatibilities. Polymeric dispersants stabilize pigments and otheringredients in paints, coatings, and ink systems via, most typically,steric stabilization. Polymeric dispersants have a two-componentstructure comprised of anchoring groups and polymeric chains. Mosttypically the anchoring groups are polar materials that interact withthe particle surfaces and the polymeric chains which are compatible withthe continuous phase of the coating. In effect, the polymeric groupsform a coating around the particles, preventing them from making contactand agglomerating into larger, incompatible aggregates.

There are many anchoring group/polymer configurations that might beexpected to give effective polymeric dispersants. The inventive resinhas polar carboxylic anchoring sites and non-polar vegetable oil chainsand can therefore act as a dispersant as well as a binder. A curingbinder that can also act as a dispersant could eliminate the need forseparate additives for dispersing many pigments.

The formulations in Table 10-6A-1 show the amounts of variousingredients based on a weight percentage.

TABLE 10-6A-1 Formulations of carbon black pigment dispersed withbio-based and commercial carboxyl functional polyester A B Type ofMaterial Specific Ingredient (wt. %) (wt. %) COOH func. Bio-basedpolyester (Example 3A product) 90.0 COOH func Control polyesterFINE-CLAD M8400 ® 90.0 Carbon black pigment Black 1300 ® (Cabot) 10.010.0

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g total formulation weight. The Brabender® mixer waspreheated to 110° C. (bowl rose to about 110° C.). 30 minutes wereallowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30.0 g of primary resin (as described in Example 3)were slowly added to the bowl; allowed to mix until melted and theremaining 33.0 g of resin was added. The resin was allowed to mix andmelt until the torque sensor showed a steady value (about 5 minutes);the speed of the mixing blades was set to 40 revolutions per minute; 7.0g of black pigment were added to center of mix zone between rotors;Mixing continued for 15 minutes. The product was removed from the mixingbowl as a black smooth, firm, shiny material and allowed to cool to roomtemperature. The material was broken into small chips with a hammer.

For the control polyester black dispersion, a total formulation weightwas calculated based on 120 ml bowl size; or about 70 g totalformulation weight. The Brabender® mixer was preheated to 110° C. (bowlrose to about 110° C.). 30 minutes were allowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30.0 g of control polyester (FineClad M8400) wereslowly added to the bowl; allowed to mix until melted and the remaining33.0 g of resin was added. The resin was allowed to mix and melt untilthe torque sensor showed a steady value (about 5 minutes); the speed ofthe mixing blades was set to 40 revolutions per minute; 7.0 g of blackpigment were added to center of mix zone between rotors; Mixingcontinued for 15 minutes. The product was removed from the mixing bowlas a black smooth, firm, shiny material and allowed to cool to roomtemperature. The material was broken into small chips with a hammer.

These materials were used in subsequent formulations to determine thedegree of dispersement of the carbon black pigment. The more dispersedthe black pigment is, the darker (blacker) the resulting color of thefinal formulation.

The formulations in Table 10-6A-2 show the amounts of variousingredients based on a weight percentage.

TABLE 10-6A-2 Formulations of bio-based and commercial carboxylfunctional polyester grey powder coatings A B Type of Material SpecificIngredient (wt. %) (wt. %) COOH func polyester FINE-CLAD M8400 ® 49.849.8 Titanium Dioxide pigment Kronos CR2310 30.0 30.0 (Kronos TitanGmbH)) Dispersed black pigment in Example A from 5.0 biobased polyestertable above Dispersed black pigment in Example B from 5.0 bio-controlpolyester table above Epoxy func acrylic FINE-CLAD A257 ® 10.2 10.2De-gas additive Benzoin 1.5 1.5 Catalyst Imidazole 0.7 0.7 Diacid curemodifier Dodecanedioic acid 2.7 2.7

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g total formulation weight. The Brabender® mixer waspreheated to 99° C. (bowl rose to about 99° C.). 30 minutes were allowedfor preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 34.9 g of primary resin (FINE-CLAD M8400®) were slowlyadded to the bowl; allowed to mix until melted. The resin was allowed tomix and melt until the torque sensor showed a steady value (about 5minutes); 22.1 g of additives (21.0 g of white pigment (Kronos 2310) and1.1 g of benzoin) were added to center of mix zone between rotors; thespeed of the rotors was set to 60 revolutions per minute and mixingcontinued for 15 minutes; 3.5 g of black pigment previously dispersed inbio-based polyester resin (Example A from Table 10-6A-2) was added andthe speed of the rotors was decreased to 40 revolutions per minute;mixing continued for 5 minutes. The 72 g of crosslinking resin (FineCladA257®) was added to the previous mixture; mixing continued for at least2 minutes, the torque reading was monitored to make sure it remainedstable in case crosslinking started) (torque reading will start to riserapidly); the torque reading was monitored closely. The catalyst wasground to a fine powder and added last (0.5 g of imidazole and 1.9 g ofdodecanedioic acid). Mixing continued for 2 minutes.

The product was removed from the mixing bowl as a grey smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C. for 30 minutes.

The control polyester powder coating total formulation weight wascalculated based on 120 ml bowl size; or about 70 g total formulationweight. The Brabender® mixer was preheated to 99° C. (bowl rose to about99° C.). 30 minutes were allowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 34.9 g of primary resin (FineClad M8400) were slowlyadded to the bowl; allowed to mix until melted. The resin was allowed tomix and melt until the torque sensor showed a steady value (about 5minutes); 22.1 g of additives (21.0 g of white pigment (Kronos 2310) and1.1 g of benzoin) were added to center of mix zone between rotors; thespeed of the rotors was set to 60 revolutions per minute and mixingcontinued for 15 minutes; 3.5 g of black pigment previously dispersed inbio-based polyester resin (Example B from Table 10-6a-2) was added andthe speed of the rotors was decreased to 40 revolutions per minute;mixing continued for 5 minutes. The 7.2 g of crosslinking resin(FineClad A257®) was added to the previous mixture; mixing continued forat least 2 minutes, the torque reading was monitored to make sure itremained stable in case crosslinking started) (torque reading will startto rise rapidly); the torque reading was monitored closely. The catalystwas ground to a fine powder and added last (0.5 g of imidazole and 1.9 gof dodecanedioic acid). Mixing continued for 2 minutes.

The product was removed from the mixing bowl as a grey smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C. for 30 minutes.

The color development and tint strength of the black pigment is improvedwith the bio-based formulation. Tint strength is the ability of the iscarbon black to darken/influence a formulation with other pigmentspresent; such as titanium dioxide. Tint strength can be determined bymeasuring the L and b color components of the coating. (For anexplanation of the Hunter color Scale see Wicks, Z. W. et al. citedabove).

Higher tint strength is determined by low L values. The lower the Lvalues, the more dispersed the carbon black and the color is betterdeveloped in the coating. The bio based polyester is better able todisperse and more fully develop the color of the carbon black to resultin a higher tint strength. Table 10-6A-3 below shows the colormeasurements from the coated panels:

TABLE 10-6A-3 Color Data Test Panel L value Bio-based 59.36Petroleum-derived 61.83

The overall Delta E, or color difference for the two black panels is2.53. The petroleum derived panel appears lighter than that of thebio-based formulation because the black pigment was not dispersed aswell into the coating system as the bio-based formulation.

Example 6B

This example illustrates a pigmented hybrid powder coating formulatedfrom with a bio-based carboxyl functional polyester of Example 3A and atriglycidyl isocyanurate (TGIC) crosslinker.

Powder coatings may also benefit if the bio-based resin has superiorability to promote the flow and leveling of the coating without theappearance if fisheyes or film defects. An example of a white powdercoating formulation (below), was made up versus a commercial control,see Table 10-6B-1. The formulations in Table 10-6B-1 show the amounts ofvarious ingredients based on a weight percentage.

TABLE 10-6B-1 Formulations of bio-based and commercial carboxylfunctional polyester white powder coatings A B Type of Material SpecificIngredient (wt. %) (wt. %) COOH func. Bio-based (Example 3A product)57.2 polyester COOH func Control Albester 5140 57.2 polyester (Hexion)TGIC crosslinker triglycidyl 4.4 4.4 isocyanurate Titanium dioxideKronos CR2310 37.9 37.9 white pigment (Kronos Titan GmbH)) De-gasadditive Benzoin 0.5 0.5

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g total formulation weight. The Brabender® mixer waspreheated to 110° C. (bowl rose to about 110° C.). 30 minutes wereallowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30 g of primary resin (as described in Example 3) wereslowly added to the bowl; allowed to mix until melted and the remaining27.2 g of resin was added. The resin was allowed to mix and melt untilthe torque sensor showed a steady value (about 5 minutes); 42.8 g ofadditives (4.4 g of TGIC, 37.9 g of titanium dioxide (Kronos CR2310) and0.5 g of benzoin) were added to center of mix zone between rotors;

Mixing continued for 10 minutes, (the torque value was monitored forstability);

The product was removed from the mixing bowl as a white smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C.

For the control polyester pigmented powder coating, a total formulationweight was calculated based on 120 ml bowl size; or about 70 g totalformulation weight. The Brabender® mixer was preheated to 110 C (bowlrose to about 110° C.). About 30 minutes were allowed for preheating.

When preheating was complete, the mixing blades were started and thetorque sensor was turned on. This acted as a guide for how the mix wasproceeding; then 30 g of primary resin (Albester 5140) were slowly addedto the bowl; allowed to mix until melted and the remaining 27.2 g ofresin was added. The resin was allowed to mix and melt until the torquesensor showed a steady value (about 5 minutes); 42.8 g of additives (4.4g of TGIC, 37.9 g of titanium dioxide (Kronos CR2310) and 0.5 g ofbenzoin) were added to center of mix zone between rotors; Mixingcontinued for 10 minutes, (the torque value was monitored forstability).

The product was removed from the mixing bowl as a white smooth, firm,shiny material and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 121° C.

TABLE 10-6B-2 Physical Properties of white powder coatings Solvent Rubs(90/10 Solvent Toluene/ Rubs Cross- MEK (MEK Pencil hatch Appear- doubledouble 60° Hard- Ad- ance rubs) rubs) Gloss ness hesion Fish- ASTM ASTMASTM ASTM ASTM eyes D5402- D5402- D523- D3363- D3359- (yes 93 93 89 0002 or no) Bio-Based 100+ 150 84.5 3H 5B No Formulation Control 90 8180.3 2H 5B yes Formulation

The bio-based formulation has better solvent resistance, higher glossand higher pencil hardness than the control formulation. The overallappearance of the bio-based formulation is much better than the controlformulation that has film defects known as “fisheyes”. The presence offisheyes in a coating is not only just an appearance problem, but sincethe substrate is exposed to the environment, these areas are susceptibleto rust and corrosion.

The resin according to another embodiment of the invention can be usedas an additive pigment to more efficiently disperse the pigment. Forexample the pigment can be added to aid in color development.

Example 7

This example illustrates the production of a hybrid powder coatingformulated with an amido-amine functional polyester and an epoxycrosslinker.

Amido-amine functional polyester powder coatings may also be formulatedwith the bio-based resin. An example of a powder coating formulation isshown below in Table 11 where the ingredient amounts are shown as weightpercentages. As there were no commercially available amido-aminefunctional polyester resins available, therefore no control was used.

TABLE 11 Powder Coating Formulations Amount Type of Material SpecificMaterial (wt %) Amido-amine func. Sample No. 36-24* 48.2 bio-basedpolyester Epoxy functional FINE-CLAD A249A ® 43.7 crosslinker CatalystImidazole 1.0 Diacid cure modifier Dodecanedioic acid 3.0 Acidic curemodifier Nacure XC7231 ® 3.0 Flow promoter Modaflow 6000 ® 1.0*Amido-amine functional resins as disclosed in WO 2004/077169, forReadily Deinkable Toners, filed Feb. 2, 2004, and designating the UnitedStates, the entire disclosure of which is incorporated herein byreference. Resin Sample No. 36-24 had a Tg of 72.5° C. and anapproximate viscosity of 1.6 × 10² Poise.

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g of total powder coatings. The Bra bender® mixer waspreheated to 99° C. (bowl rose to about 99° C.). About 30 minutes wereallowed for preheating. When preheating was complete, the mixing bladeswere started and the torque sensor was turned on. This acted as a guidefor how the mix was proceeding; then 30 g of primary resin (49251-23-22)were slowly added to the bowl. The resin was allowed to mix and meltuntil the torque sensor showed a steady value (about 5 minutes); thenthe remaining 3.7 g of primary resin was added and allowed to mix forapproximately 5 minutes. Then 0.7 g of additives (Modaflow 6000®) wasadded to center of mix zone between rotors. Mixing continued for 10minutes, (the torque value was monitored for stability). Then 30.6 g ofthe crosslinking resin (FineClad A2490) was added to the previousmixture; mixing continued for at least 3 minutes, the torque reading wasmonitored to make sure it remained stable in case crosslinking started)(torque reading will start to rise rapidly); the torque reading wasmonitored closely. The catalyst (0.7 g of imidazole, 2.1 g ofdodecanedioic acid and 2.1 g of Nacure XC-7231®) was added last,watching the torque reading closely. The torque increased and the batchwas stopped after a 10% rise in viscosity (torque).

The product was removed from the mixing bowl as a smooth, firm, shinymaterial and allowed to cool to room temperature. The material wasbroken into small chips with a hammer. Finally the product wasmicronized in a ball mill in the presence of 10 mm-15 mm steel media for16 hours. A final powder was obtained and sieved to remove any particlesover 150 microns.

The powder was electrostatically sprayed onto a 10.16 cm×15.24 cm (4inch×6 inch) bare steel panels using a Versa-Spray® manual spray gunsupplied by Nordson Corporation to a film build of approximately 76.2microns (3 mils) dry film thickness. The panels were cured in aconvection oven for 30 minutes at 95° C., 107° C. or 121° C. for 30minutes (see Table 13 for test results).

A sample from Example 7 was analyzed with the DSC, results shown inTable 12 below.

TABLE 12 Cure thermodynamics of hybrid coatings compounded frombio-based amido-amine functional polyester Tg T onset T peak of DSCResults (° C.) (tangent) (° C.) cure (° C.) Delta H Bio-based (Example7) 78.7 123 176.2 49.1 J/g

Although none of the panels had very high gloss, the film propertieswere reasonable at 107° C. cure temperature, see Table 13. The hardnessimproved dramatically as well as the solvent resistance (MEK doublerubs). The Mandrel bend results also showed improved adhesion andflexibility.

TABLE 13 Film properties of test formulations Cure Tem- Pencil Cross-3.18 mm Test per- Hard- MEK hatch (⅛ inch) formu- ature ness doubleAdhesion Forward Mandrel lation (° C.) (#) Rubs (% loss) Impact BendExample 7 95 3B 2 0 120 inch 100 mm lbs failure Example 7 107 3H 30 0160 inch 0 mm lbs failure Example 7 121 4H 80 0 160 inch 0 mm lbsfailure

Example 8

This example illustrates the production of a powder coating using abio-based polyester as a flow promoter. The polyester polymer isdescribed in EXAMPLE 3B.

First a control formulation was prepared as follows:

First a total formulation weight was calculated based on 120 ml bowlsize; or about 70 g of total powder coatings. The Brabender® mixer waspreheated to 93° C. (bowl rose to about 99° C.). About 30 minutes wereallowed for preheating. When preheating was complete, the mixing bladeswere started and the torque sensor was turned on. This acted as a guidefor how the mix was proceeding. Then 30 g of primary resin (Fine-CladM8710®) were slowly added to the bowl; the resin was allowed to mix andmelt until the torque sensor showed a steady value (about 5 minutes);then the remaining 31.8 g of primary resin was added and allowed to mixand mix for approximately 5 minutes. Then 0.44 g of additives (benzoin)was added to center of mix zone between rotors. Mixing continued for 10minutes, (the torque value was monitored for stability);

17.7 g of the crosslinking resin (FineClad A2490) was added to theprevious mixture; mixing continued for at least 3 minutes, the torquereading was monitored to make sure it remained stable in casecrosslinking started) (torque reading will start to rise rapidly); thetorque reading was monitored closely.

The product was removed from the mixing bowl as a smooth, firm, shinymaterial and allowed to cool to room temperature. The material wasbroken into small chips with a hammer.

The above procedure was repeated six more times to incorporate either 1%(on weight) or 3% (on weight) of each of three flow promoters. The flowpromoters were added at the time of benzoin addition. A bio-based flowpromoter (EXAMPLE 3B), and two commercially available flow promoters(Fine-Clad A241® and Additol VXL9820®) were used, see Table 14 below toprepare formulations B through G.

TABLE 14 Comparison of Polymeric Flow Controllers A B* C* D E F G Typeof Material Specific Material wt % wt % wt % wt % wt % wt % wt % CarboxyFINE-CLAD 77.3 76.5 75 76.5 75 76.5 75 functional M8710 ® polyesterEpoxy type FINE-CLAD 22.1 21.9 21.5 21.9 21.5 21.9 21.5 CrosslinkerA249A ® De-gas additive Bezoin 0.6 0.5 0.5 0.5 0.5 0.5 0.5 Bio-basedEXAMPLE 3B 1.0 3.0 flow promoter product Flow Promoter FINE-CLAD 1.0 3.0A241 ® Flow promoter Additol VXL9820 ® 1.0 3.0 *inventive formulation

The viscosity of the formulations in Table 14 was tested in order todetermine the effectiveness of the flow promoters in reducing theviscosity of powder coating at low cure temperatures. A lower viscositywould indicate a better flow out and smoother final film during thebake. Table 15 shows the viscosities in Poise at 90° C. to 140° C.

TABLE 15 Viscosity (Poise) Tem- per- ature (° C.) A B* C* D E F G 90376200 317430 373860 384790 437350 430130 437530 100 168310 167340172110 173270 199940 176650 198720 110 67853 76473 76455 69627 7949669476 81240 120 33261 41264 38100 32224 38617 34479 37187 130 1574222538 19801 14825 18524 16679 16757 140 10402 16724 14127 9835 1289010888 10307 *Inventive formulation

The 1% addition of the bio-based polyester flow promoter (sample B) ismost effective in reducing the viscosity of the powder coating at thelower temperatures (90° C. and 100° C.) than the other tested flowpromoters. The 3% addition at 90° C. (sample C) is still lower than thecommercially available materials. This is illustrated graphically inFIG. 7.

The DSC results from this series show that even though the meltviscosity is reduced at 90° C. and 100° C. with the addition of thebio-based flow promoter, the T_(g) of the entire powder coatingformulation was not reduced and the powder stability is not compromised.The cure peak temperature and Reaction Enthalpy (Delta H) of the powdercoating were not negatively influenced by the flow promoter. The resultsare shown in Table 16 for formulations A to G.

TABLE 16 DSC Results Property A B* C* D E F G T_(g) (° C.) 62.8 63 62.762.7 62 62.5 62.7 Cure Peak (° C.) 156.2 157.3 158 157.5 156.8 157.5 158Delta H (J/g) −32.4 −40.1 −39.9 −27.7 −38.3 −23.3 −38.5 *Inventiveformulation

Example 9

The resin of Example 3F was evaluated for its pigment dispersionproperties with color concentrates

Materials:

Two color concentrate formulas were chosen. One was a 10% loaded PB 15:3(phthalo blue) in a polystyrene carrier resin and the other was a customgreen in an acrylonitrile butadiene styrene copolymer (ABS) basedcarrier resin. The custom green consisted of a blend of organic andinorganic pigments and was about 18% loaded. Control samples were runwith typical dispersants such as zinc stearate and a combination of zincstearate and ethylene is bistearamide dispersants, and the samples wererun with the dispersant aid from Example 3F.

Compounding:

Compounding was done in a co-rotating 18 mm diameter Leistritz twinscrew extruder

Testing:

Dispersion testing was done using filter tests and the pressure build upwas reported in bar/gram of pigment. This is a quantitative test fordispersion and a lower value indicates better dispersion.

Table 17 shows the formulations used for tests and the results.

TABLE 17 Filter test value Formula Dispersion Bar/gm number PigmentCarrier resin aids pigment 6C-303295-05 10% PB 15:3 polystyrene Zincstearate 8.5 6C-303296-05 10% PB 15:3 polystyrene Example 3F 4.59C-602331-05 18% blend ABS EBS and Zinc 0.82 stearate 9C-602332-05 18%blend ABS Example 3F 0.55 PB = phtalo blue ABS = acrylonitrile butadienestyrene copolymer EBS = ethylene bistearamide

The comparison with a commercial dispersant zinc stearate, and a mixtureor EBS and zinc stearate showed good results. The results showedconstant superior color development in two different polymer systems.

While the forms of the invention herein disclosed constitute presentlypreferred embodiments, many others are possible. It is not intendedherein to mention all of the possible equivalent forms or ramificationsof the invention. It is to be understood that the terms used herein aremerely descriptive, rather than limiting, and that various changes maybe made without departing from the spirit of the scope of the invention.

1-3. (canceled)
 4. A powder coating formulation comprising the reactionproduct of a crosslinker and a carboxyl or hydroxyl functional polyesterresin comprising: the reaction product of A. a dianhydrohexitol; B. adimer diol and/or a dimer diacid; C. a diacid, diester, or diacidchloride; and D. a catalyst. 5-10. (canceled)
 11. The powder coatingformulation according to claim 4 wherein the crosslinker has epoxyfunctionality.
 12. The powder coating formulation according to claim 4wherein the crosslinker has β-hydroxy amide functionality.
 13. A coatedsubstrate comprising a substrate and a cured powder on the substrate,wherein the powder is the powder coating formulation of claim
 4. 14. Thecoated substrate according to claim 13 wherein the crosslinker has epoxyfunctionality.
 15. The coated substrate according to claim 13 whereinthe crosslinker has β-hydroxy amide functionality.
 16. The coatedsubstrate according to claim 13, wherein the powder coating provides aclass A finish.
 17. The coated substrate according to claim 13, whereinthe substrate is temperature sensitive. 18-19. (canceled)
 20. A methodfor formulating a coating composition by making a hydroxyl functionalpolyester coating resin comprising: a. selecting a tough, crystallinebio-based monomer of a dianhydrohexitol; b. co-reacting with amorphous,flowable bio-based resins to form resins comprising: A. a Tg of greaterthan about 40° C. and less than about 80° C.; B. at least 5% by weightof bio-mass in the resin composition; and C. cure, flexibility, andflow-out at low temperature bake conditions at 125° C. or less for 30minutes; and formulating the resins into coating compositions utilizinga β-hydroxy amide transesterification cure, that is the reaction of aβ-hydroxylamide curative reacting with a carboxyl group of a polyesteracid resin. 21-34. (canceled)
 35. A powder coating comprising: A. acarboxyl or hydroxyl functional coating resin comprising: the reactionproduct of a. a dianhydrohexitol; b. a dimer acid and/or a dimer diol;c. a diacid, diester, or diacid chloride; B. a crosslinker; and C. anoptional pigment.
 36. The powder coating according to claim 35,comprising a catalyst for the reaction.
 37. The powder coating accordingto claim 35, comprising a pigment dispersion aid.
 38. The powder coatingaccording to claim 35, comprising: when the resin has a carboxyl group,reacting the carboxyl group of the carboxy functionality with either aβ-hydroxylamide in a self catalyzed trans-esterification reaction orwith a polyepoxy functional polymer.
 39. The powder coating according toclaim 35, comprising: when the resin has a hydroxyl functional group,reacting the hydroxyl group of the hydroxyl functionality with an epoxyfunctional acrylic.
 40. The powder coating according to claim 35,comprising optional excipients.
 41. (canceled)